Goodwill and Other Intangible Assets - Schedule of Change in Net Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Line Items]
Balance, beginning of period	$ 3,920,060	$ 2,827,344
Acquisitions	42,540	1,149,917
Divestitures		(39,466)
Translation	6,247	(17,735)
Balance, end of period	3,968,847	3,920,060
Steel Mills [Member]
Goodwill [Line Items]
Balance, beginning of period	675,186	613,175
Acquisitions		62,011
Balance, end of period	675,186	675,186
Steel Products [Member]
Goodwill [Line Items]
Balance, beginning of period	2,510,045	1,439,874
Acquisitions	(2,120)	1,087,906
Translation	6,247	(17,735)
Balance, end of period	2,514,172	2,510,045
Raw Materials [Member]
Goodwill [Line Items]
Balance, beginning of period	734,829	774,295
Acquisitions	44,660
Divestitures		(39,466)
Balance, end of period	$ 779,489	$ 734,829