Segments - Schedule of Net Sale by Product to External Customers (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Oct. 02, 2021	Jul. 03, 2021	Apr. 03, 2021	Dec. 31, 2020	Oct. 03, 2020	Jul. 04, 2020	Apr. 04, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Net sales to external customers	$ 10,364,412	$ 10,313,223	$ 8,789,164	$ 7,017,140	$ 5,260,055	$ 4,927,960	$ 4,327,306	$ 5,624,337	$ 36,483,939	$ 20,139,658	$ 22,588,858
Sheet [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									12,675,679	5,450,507	6,450,506
Bar [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									6,039,187	3,821,158	4,106,640
Structural [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									2,597,768	1,526,283	1,573,248
Plate [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									2,832,762	1,311,360	1,803,556
Tubular Products [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									2,194,732	1,113,581	1,207,398
Rebar Fabrication [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									1,794,658	1,708,441	1,666,445
Other Steel Products [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									5,738,552	3,801,045	4,116,221
Raw Materials [Member]
Segment Reporting Information [Line Items]
Net sales to external customers									$ 2,610,601	$ 1,407,283	$ 1,664,844