Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended			9 Months Ended		12 Months Ended
	Oct. 02, 2021	Dec. 31, 2020	Oct. 03, 2020	Oct. 02, 2021	Oct. 03, 2020	Dec. 31, 2020
Finite And Indefinite Lived Intangible Assets [Line Items]
Impairment of goodwill		$ 0
Goodwill	$ 2,787,992,000	2,229,672,000		$ 2,787,992,000		$ 2,229,672,000
Finite-lived intangible assets	1,171,292,000	668,021,000		1,171,292,000		$ 668,021,000
Intangible asset amortization expense	34,800,000		$ 20,700,000	76,700,000	$ 62,900,000
Future amortization expense, in 2021	124,100,000			124,100,000
Future amortization expense, in 2022	169,900,000			169,900,000
Future amortization expense, in 2023	133,900,000			133,900,000
Future amortization expense, in 2024	133,100,000			133,100,000
Future amortization expense, in 2025	132,200,000			$ 132,200,000
Minimum [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, useful life				5 years
Maximum [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets, useful life				22 years
Rebar Fabrication [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Percentage of fair value exceeded carrying value						99.00%
Goodwill	366,200,000	364,300,000		$ 366,200,000		$ 364,300,000
Finite-lived intangible assets	52,200,000	58,800,000		52,200,000		$ 58,800,000
Grating unit [Member]
Finite And Indefinite Lived Intangible Assets [Line Items]
Percentage of fair value exceeded carrying value						88.00%
Goodwill	$ 37,100,000	$ 37,000,000.0		$ 37,100,000		$ 37,000,000.0