Statement of Changes in Consolidated Equity - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Preferred Class A	Preferred stock	Common stock	Additional capital	Retained earnings (Accumulated deficit)	Retained earnings (Accumulated deficit) Cumulative Effect, Period of Adoption, Adjustment	Retained earnings (Accumulated deficit) Preferred Class A	Accumulated other comprehensive loss	Accumulated other comprehensive loss Cumulative Effect, Period of Adoption, Adjustment	Noncontrolling Interests
Beginning balance at Dec. 31, 2018	$ 5,569	$ 73		$ 55	$ 483	$ 8,319	$ (374)	$ 75		$ (2,926)	$ (2)	$ 12
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	470						470
Other comprehensive income (loss)	(401)									(401)
Cash dividends declared:
Cash dividends declared, preferred			$ (2)						$ (2)
Cash dividends declared, common	(56)						(56)
Repurchase and retirement of common stock	(1,150)				(55)	(1,095)
Stock-based compensation	57					57
Common stock issued: compensation plans	41				5	36
Other	4					2						2
Ending balance at Dec. 31, 2019	4,605			55	433	7,319	113			(3,329)		14
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	261						261
Other comprehensive income (loss)	16									16
Cash dividends declared:
Cash dividends declared, preferred			(2)						(2)
Cash dividends declared, common	(8)						(8)
Repurchase and retirement of common stock	(73)				(3)	(70)
Stock-based compensation	45					45
Common stock issued: compensation plans	(6)				3	(9)
Distributions to Arconic Corporation	(1,261)					(2,617)				1,370		(14)
Ending balance at Dec. 31, 2020	3,577			55	433	4,668	364			(1,943)		0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	258						258
Other comprehensive income (loss)	80									80
Cash dividends declared:
Cash dividends declared, preferred			$ (2)						$ (2)
Cash dividends declared, common	(17)						(17)
Repurchase and retirement of common stock	(430)				(13)	(417)
Stock-based compensation	40					40
Common stock issued: compensation plans	2				2
Ending balance at Dec. 31, 2021	$ 3,508			$ 55	$ 422	$ 4,291	$ 603			$ (1,863)		$ 0