v3.20.1

Revenue from Contracts with Customers (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	$ 1,611	$ 1,841
Ground Transportation
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	529	682
Building and Construction
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	291	330
Aerospace
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	300	320
Industrial Products
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	298	280
Packaging
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	178	210
Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	15	19
Rolled Products
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	1,222	1,411
Rolled Products | Ground Transportation
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	499	651
Rolled Products | Building and Construction
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	35	49
Rolled Products | Aerospace
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	225	246
Rolled Products | Industrial Products
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	275	248
Rolled Products | Packaging
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	178	210
Rolled Products | Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	10	7
Extrusions
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	133	149
Extrusions | Ground Transportation
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	30	31
Extrusions | Building and Construction
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	0	0
Extrusions | Aerospace
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	75	74
Extrusions | Industrial Products
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	23	32
Extrusions | Packaging
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	0	0
Extrusions | Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	5	12
Building and Construction Systems
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	256	281
Building and Construction Systems | Ground Transportation
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	0	0
Building and Construction Systems | Building and Construction
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	256	281
Building and Construction Systems | Aerospace
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	0	0
Building and Construction Systems | Industrial Products
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	0	0
Building and Construction Systems | Packaging
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	0	0
Building and Construction Systems | Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Total end-market revenue	$ 0	$ 0

X

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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- Definition

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+ References

No definition available.

+ Details

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