Business Segment Information - Summary of Business (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)
Business Segment Information
Number of Reportable Segments | segment	4
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Net sales	$ 3,125	$ 2,785
Reconciling items
Other	(23)	(10)
Business consolidation and other activities	(7)	(115)
Amortization of acquired Rexam intangibles	(45)	(45)
Earnings before interest and taxes	300	155
Interest expense	(67)	(71)
Debt refinancing and other costs		(40)
Total interest expense	(67)	(111)
Earnings before taxes	233	44
Undistributed corporate expenses	26	14
Depreciation and Amortization
Depreciation and amortization	168	169
Capital Expenditures
Capital expenditures	363	213
Operating Segments
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Net sales	3,003	2,687
Segment Reporting Information, Operating Income (Loss) [Abstract]
Reportable segment comparable operating earnings	368	317
Operating Segments | Beverage packaging, North And Central America
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Net sales	1,296	1,181
Segment Reporting Information, Operating Income (Loss) [Abstract]
Reportable segment comparable operating earnings	140	146
Reconciling items
Business consolidation and other activities	1	(3)
Operating Segments | Beverage packaging, EMEA
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Net sales	796	669
Segment Reporting Information, Operating Income (Loss) [Abstract]
Reportable segment comparable operating earnings	100	68
Reconciling items
Business consolidation and other activities	(2)	(3)
Operating Segments | Beverage packaging, South America
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Net sales	487	405
Segment Reporting Information, Operating Income (Loss) [Abstract]
Reportable segment comparable operating earnings	93	63
Reconciling items
Business consolidation and other activities	(1)	(1)
Operating Segments | Aerospace
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Net sales	424	432
Segment Reporting Information, Operating Income (Loss) [Abstract]
Reportable segment comparable operating earnings	35	40
Other
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Net sales	122	98
Reconciling items
Business consolidation and other activities	(5)	(108)
Rexam
Reconciling items
Amortization of acquired Rexam intangibles	$ (38)	$ (37)