v3.25.3

BUSINESS COMBINATIONS - Pro Forma Information - Tabular Disclosure (Details) - Alternative Power Generation, Inc., Alternative Power Generation, Inc., and Enica Engineering, PLLC - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 03, 2025	Sep. 27, 2024	Oct. 03, 2025	Sep. 27, 2024
Business Acquisition, Pro Forma Information
Pro forma revenue	$ 182,006	$ 170,920	$ 511,736	$ 460,058
Pro forma income (loss) from operations	14,862	11,159	33,462	27,859
Pro forma net income (loss)	$ 13,721	$ 9,796	$ 33,556	$ 21,481
Earnings (loss) per share, basic (in dollars per share)	$ 0.94	$ 0.7	$ 2.33	$ 1.56
Earnings (loss) per share, diluted (in dollars per share)	$ 0.9	$ 0.68	$ 2.24	$ 1.52
Weighted average shares outstanding, basic (in shares)	14,603	13,930	14,397	13,753
Weighted average shares outstanding, diluted (in shares)	15,229	14,358	14,987	14,130

Per basic share amount, after tax, of pro forma income (loss) of combined entity as if acquisition date of business combination occurred as of beginning of period.

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Willdan Group, Inc. 10-Q