CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Statement of Comprehensive Income [Abstract]
Net earnings	$ 254,251	$ 197,725	$ 142,149
Foreign currency translation adjustments:
Unrealized translation gains (losses)	(44,741)	(31,405)	21,483
Realized loss on offshore wind energy structures business recorded in other expense	25,977
Foreign currency translation adjustments	(18,764)	(31,405)	21,483
Gain (loss) on hedging activities:
Commodity hedges	(2,352)	20,019
Realized (gain) loss on commodity hedges recorded in earnings	5,212	(25,821)
Unrealized gain (loss) on cross currency swaps	5,146	6,093	(5,751)
Unrealized gain on net investment hedges, net of tax expense of $2,428 in 2020			7,289
Realized (gain) on offshore wind energy structures business cross currency swap, net of tax expense of $1,207 in 2022	(3,620)
Cash flow hedges			1,598
Realized gain on cash flow hedges recorded in earnings			(1,598)
Amortization cost included in interest expense	(64)	(64)	(64)
Gain (loss) on hedging activities	4,322	227	1,474
Net gain (loss) on defined benefit pension plan, net of tax expense (benefit) of $(606) in 2022, $25,736 in 2021, $(4,183) in 2020	1,345	76,718	(17,349)
Other comprehensive income (loss)	(13,097)	45,540	5,608
Comprehensive income	241,154	243,265	147,757
Comprehensive income attributable to noncontrolling interests	(2,073)	(976)	(3,428)
Comprehensive income attributable to Valmont Industries, Inc.	$ 239,081	$ 242,289	$ 144,329