Goodwill and Other Intangible Assets - Schedule of Change in Net Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Goodwill [Line Items]
Balance, beginning of period	$ 3,969	$ 3,920
Acquisitions	335	43
Translation	(16)	6
Balance, end of period	4,288	3,969
Steel Mills [Member]
Goodwill [Line Items]
Balance, beginning of period	675	675
Balance, end of period	675	675
Steel Products [Member]
Goodwill [Line Items]
Balance, beginning of period	2,514	2,510
Acquisitions	318	(2)
Translation	(16)	6
Balance, end of period	2,816	2,514
Raw Materials [Member]
Goodwill [Line Items]
Balance, beginning of period	780	735
Acquisitions	17	45
Balance, end of period	$ 797	$ 780