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The performance conditions applicable to the award were determined to have been satisfied by the Issuer's Compensation Committee effective on March 25, 2026, resulting in the immediate vesting of the restricted stock units as to 3,780 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 4,500 shares of restricted stock units that vest in three substantially equal installments on each of March 3, 2027, March 3, 2028 and March 3, 2029, (ii) 3,080 shares of restricted stock units that vest in two substantially equal installments on each of March 17, 2027 and March 17, 2028, and (iii) 1,400 shares of restricted stock units that vest on March 20, 2027, subject to the Reporting Person's continued service to the Issuer through the applicable vesting 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on each of March 20, 2026 and March 20, 2027, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":48545,"source":{"system":"sec-edgar","filing":"0001733678-26-000010","document":"form4-03192026_090337.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000173367826000010/form4-03192026_090337.xml","form_type":"4"}},{"id":837181,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EXECUTIVE VP & GENERAL COUNSEL"}}],"security":"Common 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The performance conditions applicable to the award were determined to have been satisfied by the Issuer's Compensation Committee on July 30, 2024, resulting in the immediate vesting of the restricted stock units as to 1,736 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 4,200 shares of restricted stock units that vest in three substantially equal installments on each of March 20, 2025, March 20, 2026 and March 20, 2027 and (ii) 1,867 shares of restricted stock that vest in two substantially equal installments on each of March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 683 shares of Common Stock purchased under the Amended and Restated Willdan Group, Inc. 2006 Employee Stock Purchase Plan on June 30, 2024."}],"balance_after":31917,"source":{"system":"sec-edgar","filing":"0001415889-24-021840","document":"form4-08212024_090853.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588924021840/form4-08212024_090853.xml","form_type":"4"}},{"id":1563110,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EXECUTIVE VP & GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2024-03-22T21:36:30.000Z","date":"2024-03-20","kind":"tax_withholding","planned":false,"acquired":false,"shares":1412,"price":27.55,"value":38900.6,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F4","text":"Represents shares of the Issuer's Common Stock withheld to satisfy tax withholding obligations in connection with the vesting of the performance-based restricted stock units referenced in footnote (3)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 4,200 shares of restricted stock units that vest in three substantially equal installments on each of March 20, 2025, March 20, 2026 and March 20, 2027 and (ii) 1,867 shares of restricted stock that vest in two substantially equal installments on each of March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":29498,"source":{"system":"sec-edgar","filing":"0001415889-24-009002","document":"form4-03222024_090324.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588924009002/form4-03222024_090324.xml","form_type":"4"}},{"id":1563109,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"EXECUTIVE VP & GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2024-03-22T21:36:30.000Z","date":"2024-03-20","kind":"grant","planned":false,"acquired":true,"shares":2520,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F3","text":"Represents performance-based restricted stock units previously granted to the Reporting Person by the Issuer on March 7, 2023. The performance conditions applicable to the award were determined to have been satisfied by the Issuer's Compensation Committee on March 20, 2024, resulting in the immediate vesting of the restricted stock units as to 2,520 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 4,200 shares of restricted stock units that vest in three substantially equal installments on each of March 20, 2025, March 20, 2026 and March 20, 2027 and (ii) 1,867 shares of restricted stock that vest in two substantially equal installments on each of March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting 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restricted stock units awarded to the Reporting Person by the Issuer on March 20, 2024, which vest in three substantially equal installments on each of March 20, 2025, March 20, 2026 and March 20, 2027, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 4,200 shares of restricted stock units that vest in three substantially equal installments on each of March 20, 2025, March 20, 2026 and March 20, 2027 and (ii) 1,867 shares of restricted stock that vest in two substantially equal installments on each of March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting 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Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24190,"source":{"system":"sec-edgar","filing":"0001415889-24-007544","document":"form4-03112024_100357.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588924007544/form4-03112024_100357.xml","form_type":"4"}},{"id":1795084,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common 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These shares were sold in multiple transactions at prices ranging from $24.68 to $24.75, inclusive."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24175,"source":{"system":"sec-edgar","filing":"0001415889-23-012724","document":"form4-08282023_100803.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923012724/form4-08282023_100803.xml","form_type":"4"}},{"id":1795083,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-08-28T22:19:10.000Z","date":"2023-08-24","kind":"sale","planned":false,"acquired":false,"shares":242,"price":24.34,"value":5890.28,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of the performance-based restricted stock units on August 21, 2023."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $23.67 to $24.65,\ninclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (2) and footnote (4)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24191,"source":{"system":"sec-edgar","filing":"0001415889-23-012724","document":"form4-08282023_100803.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923012724/form4-08282023_100803.xml","form_type":"4"}},{"id":1797482,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-08-24T21:38:33.000Z","date":"2023-08-23","kind":"sale","planned":false,"acquired":false,"shares":126,"price":23.81,"value":3000.06,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of the performance-based restricted stock units on August 21, 2023."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $23.65 to $24.15, inclusive."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24433,"source":{"system":"sec-edgar","filing":"0001415889-23-012614","document":"form4-08242023_090826.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923012614/form4-08242023_090826.xml","form_type":"4"}},{"id":1797481,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-08-24T21:38:33.000Z","date":"2023-08-23","kind":"sale","planned":false,"acquired":false,"shares":169,"price":23.29,"value":3936.01,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of the performance-based restricted stock units on August 21, 2023."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $22.65 to $23.64, inclusive."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24559,"source":{"system":"sec-edgar","filing":"0001415889-23-012614","document":"form4-08242023_090826.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923012614/form4-08242023_090826.xml","form_type":"4"}},{"id":1797480,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-08-24T21:38:33.000Z","date":"2023-08-22","kind":"sale","planned":false,"acquired":false,"shares":305,"price":22.82,"value":6960.1,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of the performance-based restricted stock units on August 21, 2023."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $22.60 to $23.09, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (2), footnote (4) and footnote (5)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24728,"source":{"system":"sec-edgar","filing":"0001415889-23-012614","document":"form4-08242023_090826.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923012614/form4-08242023_090826.xml","form_type":"4"}},{"id":1799493,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-08-22T22:10:08.000Z","date":"2023-08-21","kind":"grant","planned":false,"acquired":true,"shares":1736,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents performance-based restricted stock units previously granted to the Reporting Person by the Issuer on August 2, 2022. The performance conditions\napplicable to the award were determined to have been satisfied by the Issuer's Compensation Committee on August 21, 2023, resulting in the immediate vesting of the restricted stock units as to 1,736 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 823 shares of Common Stock purchased under the Amended and Restated Willdan Group, Inc. 2006 Employee Stock Purchase Plan on June 30, 2023."}],"balance_after":25033,"source":{"system":"sec-edgar","filing":"0001415889-23-012509","document":"form4-08222023_100802.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923012509/form4-08222023_100802.xml","form_type":"4"}},{"id":1902293,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-05-05T22:02:18.000Z","date":"2023-05-04","kind":"tax_withholding","planned":false,"acquired":false,"shares":1241,"price":14.35,"value":17808.35,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock withheld for tax withholding purposes in connection with the vesting of restricted stock on May 4, 2023, which restricted stock was granted on May 4, 2021."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":22474,"source":{"system":"sec-edgar","filing":"0001415889-23-007478","document":"form4-05052023_100512.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923007478/form4-05052023_100512.xml","form_type":"4"}},{"id":1953785,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-03-15T00:13:05.000Z","date":"2023-03-13","kind":"sale","acquired":false,"shares":294,"price":16.77,"value":4930.38,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of restricted stock on March 8, 2023, which restricted stock was granted on March 8, 2022."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $16.54 to $17.04, inclusive."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026 and (ii) 2,500 shares of restricted stock that vest on May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":23715,"source":{"system":"sec-edgar","filing":"0001415889-23-004910","document":"form4-03152023_120359.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923004910/form4-03152023_120359.xml","form_type":"4"}},{"id":1953784,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-03-15T00:13:05.000Z","date":"2023-03-13","kind":"sale","acquired":false,"shares":471,"price":16.15,"value":7606.65,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of restricted stock on March 8, 2023, which restricted stock was granted on March 8, 2022."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $15.53 to $16.52, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (2) and footnote (4)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026 and (ii) 2,500 shares of restricted stock that vest on May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24009,"source":{"system":"sec-edgar","filing":"0001415889-23-004910","document":"form4-03152023_120359.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923004910/form4-03152023_120359.xml","form_type":"4"}},{"id":1956469,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-03-13T22:45:13.000Z","date":"2023-03-10","kind":"sale","acquired":false,"shares":69,"price":16.96,"value":1170.24,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of restricted stock on March 8, 2023, which restricted stock was granted on March 8, 2022."},{"field":"price","element":"transactionPricePerShare","label":"F5","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $16.60 to $17.00, inclusive."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026 and (ii) 2,500 shares of restricted stock that vest on May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24480,"source":{"system":"sec-edgar","filing":"0001415889-23-004809","document":"form4-03132023_100306.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923004809/form4-03132023_100306.xml","form_type":"4"}},{"id":1956468,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-03-13T22:45:13.000Z","date":"2023-03-10","kind":"sale","acquired":false,"shares":311,"price":15.78,"value":4907.58,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of restricted stock on March 8, 2023, which restricted stock was granted on March 8, 2022."},{"field":"price","element":"transactionPricePerShare","label":"F4","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $15.56 to $16.53, inclusive."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026 and (ii) 2,500 shares of restricted stock that vest on May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24549,"source":{"system":"sec-edgar","filing":"0001415889-23-004809","document":"form4-03132023_100306.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923004809/form4-03132023_100306.xml","form_type":"4"}},{"id":1956467,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-03-13T22:45:13.000Z","date":"2023-03-10","kind":"sale","acquired":false,"shares":350,"price":15.21,"value":5323.5,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of restricted stock on March 8, 2023, which restricted stock was granted on March 8, 2022."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $14.55 to $15.53, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote (2), footnote (4) and footnote (5)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026 and (ii) 2,500 shares of restricted stock that vest on May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24860,"source":{"system":"sec-edgar","filing":"0001415889-23-004809","document":"form4-03132023_100306.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923004809/form4-03132023_100306.xml","form_type":"4"}},{"id":1958483,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-03-10T23:05:42.000Z","date":"2023-03-09","kind":"sale","acquired":false,"shares":786,"price":17.03,"value":13385.58,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of restricted stock on March 8, 2023, which restricted stock was granted on March 8, 2022."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $16.90 to $17.35, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 2,800 shares of restricted stock that vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026 and (ii) 2,500 shares of restricted stock that vest on May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":25210,"source":{"system":"sec-edgar","filing":"0001415889-23-004686","document":"form4-03102023_110337.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923004686/form4-03102023_110337.xml","form_type":"4"}},{"id":1962755,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2023-03-08T23:41:57.000Z","date":"2023-03-07","kind":"grant","acquired":true,"shares":2800,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of restricted stock awarded to the Reporting Person by the Issuer on March 7, 2023, which vest in three substantially equal installments on each of March 7, 2024, March 7, 2025 and March 7, 2026, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 2,500 shares of restricted stock that vest on May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes an aggregate of 771 shares of Common Stock purchased under the Amended and Restated Willdan Group, Inc. 2006 Employee Stock Purchase Plan, including 533 shares on June 30, 2022 and 238 shares on December 31, 2022."}],"balance_after":25996,"source":{"system":"sec-edgar","filing":"0001415889-23-004541","document":"form4-03082023_110351.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588923004541/form4-03082023_110351.xml","form_type":"4"}},{"id":2279065,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-05-06T22:02:50.000Z","date":"2022-05-04","kind":"tax_withholding","acquired":false,"shares":1240,"price":29.58,"value":36679.2,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of the Issuer's Common Stock withheld for tax withholding purposes in connection with the vesting of restricted stock on May 4, 2022, which restricted stock was granted on May 4, 2021."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 2,500 shares of restricted stock that vest on May 4, 2023 and (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":22425,"source":{"system":"sec-edgar","filing":"0001415889-22-004751","document":"form4-05062022_030533.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922004751/form4-05062022_030533.xml","form_type":"4"}},{"id":2314031,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-30T21:32:50.000Z","date":"2022-03-28","kind":"tax_withholding","acquired":false,"shares":560,"price":30.84,"value":17270.4,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F5","text":"Represents shares of the Issuer's Common Stock withheld for tax withholding purposes in connection with the vesting of the performance-based restricted stock units referenced in footnote (3)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 5,000 shares of restricted stock that vest in two substantially equal installments on each of May 4, 2022 and May 4, 2023 and (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":23665,"source":{"system":"sec-edgar","filing":"0001415889-22-003480","document":"form4-03302022_020334.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":4,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922003480/form4-03302022_020334.xml","form_type":"4"}},{"id":2314030,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-30T21:32:50.000Z","date":"2022-03-28","kind":"tax_withholding","acquired":false,"shares":588,"price":30.84,"value":18133.92,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F4","text":"Represents shares of the Issuer's Common Stock withheld for tax withholding purposes in connection with the vesting of the performance-based restricted stock units referenced in footnote (1)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 5,000 shares of restricted stock that vest in two substantially equal installments on each of May 4, 2022 and May 4, 2023 and (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24225,"source":{"system":"sec-edgar","filing":"0001415889-22-003480","document":"form4-03302022_020334.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922003480/form4-03302022_020334.xml","form_type":"4"}},{"id":2314029,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-30T21:32:50.000Z","date":"2022-03-28","kind":"grant","acquired":true,"shares":1254,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F3","text":"Represents performance-based restricted stock units previously granted to the Reporting Person by the Issuer on March 2, 2020. The performance conditions applicable to the award were determined to have been satisfied by the Issuer's Compensation Committee on March 28, 2022, resulting in the immediate vesting of the restricted stock units as to 1,254 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 5,000 shares of restricted stock that vest in two substantially equal installments on each of May 4, 2022 and May 4, 2023 and (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":24813,"source":{"system":"sec-edgar","filing":"0001415889-22-003480","document":"form4-03302022_020334.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922003480/form4-03302022_020334.xml","form_type":"4"}},{"id":2314028,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-30T21:32:50.000Z","date":"2022-03-28","kind":"grant","acquired":true,"shares":1316,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents performance-based restricted stock units previously granted to the Reporting Person by the Issuer on March 6, 2018. The performance conditions applicable to the award were determined to have been satisfied by the Issuer's Compensation Committee on March 28, 2022, resulting in the immediate vesting of the restricted stock units as to 1,316 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 5,000 shares of restricted stock that vest in two substantially equal installments on each of May 4, 2022 and May 4, 2023 and (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":23559,"source":{"system":"sec-edgar","filing":"0001415889-22-003480","document":"form4-03302022_020334.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922003480/form4-03302022_020334.xml","form_type":"4"}},{"id":2326606,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-17T23:24:44.000Z","date":"2022-03-15","kind":"sale","acquired":false,"shares":3830,"price":28.19,"value":107967.7,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of the performance-based restricted stock units on March 14, 2022."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 5,000 shares of restricted stock that vest in two substantially equal installments on each of May 4, 2022 and May 4, 2023 and (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":22243,"source":{"system":"sec-edgar","filing":"0001415889-22-003150","document":"form4-03172022_040332.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922003150/form4-03172022_040332.xml","form_type":"4"}},{"id":2326605,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-17T23:24:44.000Z","date":"2022-03-15","kind":"sale","acquired":false,"shares":356,"price":26.44,"value":9412.64,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of the performance-based restricted stock units on March 14, 2022."},{"field":"price","element":"transactionPricePerShare","label":"F2","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $26.43 to $27.10, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes (i) 5,000 shares of restricted stock that vest in two substantially equal installments on each of May 4, 2022 and May 4, 2023 and (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":26073,"source":{"system":"sec-edgar","filing":"0001415889-22-003150","document":"form4-03172022_040332.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922003150/form4-03172022_040332.xml","form_type":"4"}},{"id":2330378,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-16T23:14:27.000Z","date":"2022-03-14","kind":"grant","acquired":true,"shares":8007,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents performance-based restricted stock units previously granted to the Reporting Person by the Issuer on March 9, 2021. The performance conditions applicable to the award were determined to have been satisfied by the Issuer's Compensation Committee on March 14, 2022, resulting in the immediate vesting of the restricted stock units as to 8,007 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes (i) 5,000 shares of restricted stock that vest in two substantially equal installments on each of May 4, 2022 and May 4, 2023 and  (ii) 3,800 shares of restricted stock that vest on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":26429,"source":{"system":"sec-edgar","filing":"0001415889-22-003077","document":"form4-03162022_040318.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922003077/form4-03162022_040318.xml","form_type":"4"}},{"id":2339470,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2022-03-11T00:42:22.000Z","date":"2022-03-08","kind":"grant","acquired":true,"shares":3800,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of restricted stock awarded to the Reporting Person by the Issuer on March 8, 2022, which vests in one installment on March 8, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 5,000 shares of restricted stock that vest in two equal installments on each of May 4, 2022 and May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 225 shares of Common Stock purchased under the Amended and Restated Willdan Group, Inc. 2006 Employee Stock Purchase Plan on December 31, 2021"}],"balance_after":18422,"source":{"system":"sec-edgar","filing":"0001415889-22-002853","document":"form4-03102022_040306.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588922002853/form4-03102022_040306.xml","form_type":"4"}},{"id":2463612,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"GENERAL COUNSEL"}}],"security":"Common Stock","published_at":"2021-12-20T23:26:56.000Z","date":"2021-12-17","kind":"sale","acquired":false,"shares":5037,"price":41.01,"value":206567.37,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $40.74 to $41.32, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 5,000 shares of restricted stock that vest in two equal installments on each of May 4, 2022 and May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 390 shares of Common Stock purchased under the Amended and Restated Willdan Group, Inc. 2006 Employee Stock Purchase Plan on June 30, 2021."}],"balance_after":14397,"source":{"system":"sec-edgar","filing":"0001415889-21-006133","document":"form4-12202021_031247.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000141588921006133/form4-12202021_031247.xml","form_type":"4"}},{"id":2660330,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Common Stock","published_at":"2021-06-21T22:15:11.000Z","date":"2021-06-17","kind":"sale","acquired":false,"shares":2000,"price":37.92,"value":75840.0,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $37.80 to $38.05, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 5,000 shares of restricted stock that vest in two equal installments on each of May 4, 2022 and May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":19044,"source":{"system":"sec-edgar","filing":"0001179110-21-006938","document":"edgar.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000117911021006938/edgar.xml","form_type":"4"}},{"id":2663136,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Common Stock","published_at":"2021-06-17T22:19:40.000Z","date":"2021-06-16","kind":"sale","acquired":false,"shares":1664,"price":39.23,"value":65278.72,"ownership":{"direct":true},"footnotes":[{"field":"price","element":"transactionPricePerShare","label":"F1","text":"The price reported in Column 4 is the weighted average price. These shares were sold in multiple transactions at prices ranging from $38.96 to $39.63, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F2","text":"Includes 5,000 shares of restricted stock that vest in two equal installments on each of May 4, 2022 and May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":21044,"source":{"system":"sec-edgar","filing":"0001179110-21-006832","document":"edgar.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000117911021006832/edgar.xml","form_type":"4"}},{"id":2671458,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Common Stock","published_at":"2021-06-11T23:05:23.000Z","date":"2021-06-09","kind":"tax_withholding","acquired":false,"shares":3007,"price":39.27,"value":118084.89,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F4","text":"Represents shares of the Issuer's Common Stock withheld for tax withholding purposes in connection with the vesting of the performance-based restricted stock units referenced in footnote (2)."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 5,000 shares of restricted stock that vest in two equal installments on each of May 4, 2022 and May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":22708,"source":{"system":"sec-edgar","filing":"0001179110-21-006631","document":"edgar.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":3,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000117911021006631/edgar.xml","form_type":"4"}},{"id":2671457,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Common Stock","published_at":"2021-06-11T23:05:23.000Z","date":"2021-06-09","kind":"grant","acquired":true,"shares":6744,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F2","text":"Represents performance-based restricted stock units previously granted to the Reporting Person by the Issuer on June 13, 2019. The performance conditions applicable to the award were determined to have been satisfied by the Issuer's Compensation Committee on June 9, 2021, resulting in the immediate vesting of the restricted stock units as to 6,744 shares of Common Stock."},{"field":"balance_after","element":"sharesOwnedFollowingTransaction","label":"F3","text":"Includes 5,000 shares of restricted stock that vest in two equal installments on each of May 4, 2022 and May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":25715,"source":{"system":"sec-edgar","filing":"0001179110-21-006631","document":"edgar.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":2,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000117911021006631/edgar.xml","form_type":"4"}},{"id":2671456,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Common Stock","published_at":"2021-06-11T23:05:23.000Z","date":"2021-05-04","kind":"grant","acquired":true,"shares":5000,"price":0,"value":0.0,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of restricted stock awarded to the Reporting Person by the Issuer on May 4, 2021, which vest in two equal installments on each of May 4, 2022 and May 4, 2023, subject to the Reporting Person's continued service to the Issuer through the applicable vesting date."}],"balance_after":18971,"source":{"system":"sec-edgar","filing":"0001179110-21-006631","document":"edgar.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":1,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000117911021006631/edgar.xml","form_type":"4"}},{"id":2770343,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Common Stock","published_at":"2021-03-26T22:02:34.000Z","date":"2021-03-24","kind":"sale","acquired":false,"shares":7,"price":37.99,"value":265.93,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of performance- based restricted stock units on March 19, 2021."},{"field":"price","element":"transactionPricePerShare","label":"F10","text":"The price reported in Column 4 is the weighted average price. 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These shares were sold in multiple transactions at prices ranging from $35.77 to $36.76, inclusive."}],"balance_after":14149,"source":{"system":"sec-edgar","filing":"0001179110-21-003828","document":"edgar.xml","document_sequence":1,"table":"nonDerivative","row_type":"transaction","position":7,"url":"https://www.sec.gov/Archives/edgar/data/1370450/000117911021003828/edgar.xml","form_type":"4"}},{"id":2770340,"issuer":{"id":4758,"kind":"organization","name":"Willdan Group, Inc.","symbol":"WLDN"},"owners":[{"id":55803,"kind":"person","name":"CHEN MICAH","position":1,"cik":"0001733678","reported_name":"CHEN MICAH","relationship":{"director":false,"officer":true,"ten_percent_owner":false,"other":false,"officer_title":"General Counsel"}}],"security":"Common Stock","published_at":"2021-03-26T22:02:34.000Z","date":"2021-03-24","kind":"sale","acquired":false,"shares":356,"price":34.99,"value":12456.44,"ownership":{"direct":true},"footnotes":[{"field":"shares","element":"transactionShares","label":"F1","text":"Represents shares of Common Stock sold in the open market, the proceeds of which were used to pay the tax withholding obligations incurred upon the vesting of performance- based restricted stock units on March 19, 2021."},{"field":"price","element":"transactionPricePerShare","label":"F7","text":"The price reported in Column 4 is the weighted average price. 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These shares were sold in multiple transactions at prices ranging from $39.82 to $40.74, inclusive. 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