CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Millions		Total		Common stock:	Treasury stock:	Additional paid-in capital:	Retained earnings:	Accumulated other comprehensive income (loss):	Pension and other benefit adjustments (Note 18):		Foreign currency translation adjustments:		Derivative financial instruments:	Total stockholders’ equity	Noncontrolling interests:
Balance at beginning of year at Dec. 31, 2018				$ 177	$ (78)	$ 3,917	$ 1,212		$ (1,416)		$ 403		$ (13)		$ 1
Balance at beginning of year (in shares) at Dec. 31, 2018				177,386,000	(2,858,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued				$ 2		0
Common stock issued (in shares)				1,169,000
Common stock repurchased		$ (88)			$ (88)
Common stock repurchased (in shares)		(5,289,475)			(5,289,000)
Common stock (repurchased) reissued for employee/non-employee director stock plans					$ (7)
Common stock (repurchased) reissued for employee/non-employee director stock plans (in shares)					(362,000)
Dividends on common stock						0	(35)
Issuance of conversion option in 2026 Senior Convertible Notes, net of tax						77
Employee stock plans						26
Net earnings (loss) attributable to United States Steel Corporation		$ (630)					(630)
Other							(3)								0
Changes in pension and other employee benefit accounts (a)		573	[1]						580	[2]
Changes during year, equity investee net of taxes (a)	[2]								(7)
Changes in foreign currency translation adjustments (a)		(22)	[1]								(22)	[2]
Derivative reclassifications to Consolidated Statements of Operations	[2]												(3)
Stelco Option Agreement															0
Net loss															0
Balance at end of year at Dec. 31, 2019				$ 179	$ (173)	4,020	544	$ (478)	(843)		381		(16)	$ 4,092	1
Balance at end of year (in shares) at Dec. 31, 2019				178,555,000	(8,509,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive (loss) income including noncontrolling interest		(82)
Related Income Tax Benefit (Provision):
Foreign currency translation adjustments		6
Pension and other benefits adjustments		(191)
Derivative adjustments		1
Common stock issued				$ 50		360
Common stock issued (in shares)				50,551,000
Common stock repurchased					$ 0
Common stock repurchased (in shares)					0
Common stock (repurchased) reissued for employee/non-employee director stock plans					$ (2)
Common stock (repurchased) reissued for employee/non-employee director stock plans (in shares)					(164,000)
Dividends on common stock						(6)	(2)
Issuance of conversion option in 2026 Senior Convertible Notes, net of tax						0
Employee stock plans						28
Net earnings (loss) attributable to United States Steel Corporation		(1,165)					(1,165)
Other							0								(1)
Changes in pension and other employee benefit accounts (a)		385	[1]						360	[2]
Changes during year, equity investee net of taxes (a)	[2]								25
Changes in foreign currency translation adjustments (a)		68	[1]								68	[2]
Derivative reclassifications to Consolidated Statements of Operations	[2]												(22)
Stelco Option Agreement															93
Net loss															0
Balance at end of year at Dec. 31, 2020		3,786		$ 229	$ (175)	4,402	(623)	(47)	(458)		449		(38)	3,786	93
Balance at end of year (in shares) at Dec. 31, 2020				229,106,000	(8,673,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive (loss) income including noncontrolling interest		(734)
Related Income Tax Benefit (Provision):
Foreign currency translation adjustments		(16)
Pension and other benefits adjustments		(123)
Derivative adjustments		4
Common stock issued				$ 51		742
Common stock issued (in shares)				50,416,000
Common stock repurchased		$ (150)			$ (150)
Common stock repurchased (in shares)		(6,556,855)			(6,557,000)
Common stock (repurchased) reissued for employee/non-employee director stock plans					$ (9)
Common stock (repurchased) reissued for employee/non-employee director stock plans (in shares)					(479,000)
Dividends on common stock						(5)	(18)
Issuance of conversion option in 2026 Senior Convertible Notes, net of tax						0
Employee stock plans						60
Net earnings (loss) attributable to United States Steel Corporation		$ 4,174					4,174
Other							1								0
Changes in pension and other employee benefit accounts (a)		433	[1]						433	[2]
Changes during year, equity investee net of taxes (a)	[2]								0
Changes in foreign currency translation adjustments (a)		(78)	[1]								(78)	[2]
Derivative reclassifications to Consolidated Statements of Operations	[2]												23
Stelco Option Agreement															0
Net loss															0
Balance at end of year at Dec. 31, 2021		9,010		$ 280	$ (334)	$ 5,199	$ 3,534	$ 331	$ (25)		$ 371		$ (15)	$ 9,010	$ 93
Balance at end of year (in shares) at Dec. 31, 2021				279,522,000	(15,709,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive (loss) income including noncontrolling interest		4,552
Related Income Tax Benefit (Provision):
Foreign currency translation adjustments		32
Pension and other benefits adjustments		(147)
Derivative adjustments		$ (6)

[1] Related income tax (provision) benefit Foreign currency translation adjustments$32 $(16)$6 Pension and other benefits adjustments(147)(123)(191)Derivative adjustments(6)4 1 

[2] Related income tax benefit (provision): Foreign currency translation adjustments$32 $(16)$6 Pension and other benefits adjustments(147)(123)(191)Derivative adjustments (6)4 1