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Revenue - Summary of Revenue by Product Line (Detail) - EUR (€) € in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disclosure of products and services [line items]
Revenue	€ 1,538	€ 1,474	€ 3,074	€ 2,860
Packaging rolled products [member]
Disclosure of products and services [line items]
Revenue	568	589	1,116	1,125
Automotive rolled products [member]
Disclosure of products and services [line items]
Revenue	209	163	439	318
Specialty and other thin-rolled products [member]
Disclosure of products and services [line items]
Revenue	42	47	90	92
Aerospace rolled products [member]
Disclosure of products and services [line items]
Revenue	224	197	429	376
Transportation, Industry and other rolled products [member]
Disclosure of products and services [line items]
Revenue	148	148	310	300
Automotive extruded products [member]
Disclosure of products and services [line items]
Revenue	199	178	387	347
Other extruded products [member]
Disclosure of products and services [line items]
Revenue	€ 148	148	€ 303	296
Other [member]
Disclosure of products and services [line items]
Revenue		€ 4		€ 6

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- Definition

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The income arising in the course of an entity's ordinary activities. Income is increases in economic benefits during the accounting period in the form of inflows or enhancements of assets or decreases of liabilities that result in an increase in equity, other than those relating to contributions from equity participants.

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