CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 197,725	$ 142,149	$ 152,105
Foreign currency translation adjustments:
Unrealized translation gains (losses)	(31,405)	21,483	(2,506)
Foreign currency translation adjustments	(31,405)	21,483	(2,506)
Gain/(loss) on hedging activities:
Commodity hedges	20,019	0	(2,130)
Realized (gain) loss on commodity hedges recorded in earnings	(25,821)	0	2,130
Unrealized gain (loss) on cross currency swaps	6,093	(5,751)	1,815
Cash flow hedges	0	1,598	0
Realized (gain) loss on cash flow hedges recorded in earnings	0	(1,598)	0
Amortization cost included in interest expense	(64)	(64)	(64)
Unrealized gain on net investment hedges, net of tax expense (benefit) of $— in 2021, $2,428 in 2020, $384 in 2019	0	7,289	1,154
Other Comprehensive Income Loss, Hedging Activities, Gain (loss), after Reclassification and Tax	227	1,474	2,905
Actuarial gain (loss) on defined benefit pension plan, net of tax expense (benefit) of $25,736 in 2021, $(4,183) in 2020, $(2,710) in 2019	76,718	(17,349)	(10,828)
Other comprehensive income (loss)	45,540	5,608	(10,429)
Comprehensive income	243,265	147,757	141,676
Comprehensive (income) loss attributable to noncontrolling interests	(976)	(3,428)	(5,505)
Comprehensive income attributable to Valmont Industries, Inc.	$ 242,289	$ 144,329	$ 136,171