Statement of Consolidated Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Sales	$ 4,972	$ 5,259	$ 7,098
Cost of goods sold (exclusive of expenses below)	3,596	3,878	5,214
Selling, general administrative, and other expenses	251	277	400
Research and development expenses	17	17	28
Provision for depreciation and amortization	270	279	295
Restructuring and other charges	90	182	582
Operating income	748	626	579
Loss on debt redemption	146	64	0
Amount charged to interest expense, net	259	317	338
Other expense, net	19	74	31
Income before income taxes	324	171	210
Provision (benefit) for income taxes	66	(40)	84
Net income from continuing operations attributable to common shareholders	258	211	126
Income from discontinued operations after income taxes	0	50	344
Net income	258	261	470
Amounts Attributable to Howmet Aerospace Inc. Common Shareholders:
Net income	$ 256	$ 259	$ 477
Earnings per share - basic
Continuing operations (in usd per share)	$ 0.60	$ 0.48	$ 0.28
Discontinued operations (in usd per share)	0	0.11	0.77
Earnings per share - diluted
Continuing operations (in usd per share)	0.59	0.48	0.27
Discontinued operations (in usd per share)	$ 0	$ 0.11	$ 0.76
Average Shares Outstanding:
Average shares outstanding - basic (in shares)	430	435	446
Average shares outstanding - diluted (in shares)	435	439	463