SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	$ 3,501,575	$ 2,895,355	$ 2,766,976
Contract assets	142,643	123,495
Contract liabilities	213,203	170,919
Contract liabilities, current	135,746	130,018
Revenue recognized from contract liability	105,406	74,319
Remaining performance obligation	165,657
Contract Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract liabilities, current	135,746
Other Noncurrent Liabilities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract liabilities, noncurrent	77,457
Utility Support Structures
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	1,121,004	1,002,138	885,608
Engineered Support Structures
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	1,064,440	983,523	1,002,076
Coatings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales		269,602	300,640
Irrigation
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	1,017,050	640,092	578,652
Point in Time
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	2,384,575	1,921,328	1,865,064
Point in Time | Utility Support Structures
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	62,904	86,382	47,450
Point in Time | Engineered Support Structures
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	1,026,312	940,513	952,056
Point in Time | Coatings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	299,081	269,602	300,640
Point in Time | Irrigation
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	996,278	624,831	564,918
Over Time
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	1,117,000	974,027	901,912
Over Time | Utility Support Structures
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	1,058,100	915,756	838,158
Over Time | Engineered Support Structures
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	38,128	43,010	50,020
Over Time | Coatings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	0	0	0
Over Time | Irrigation
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net sales	$ 20,772	$ 15,261	$ 13,734
Minimum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected timing of performance obligation satisfaction	12 months
Maximum
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected timing of performance obligation satisfaction	24 months