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Operating Segment Information - Summary of Segment Capital Expenditures (Detail) - EUR (€) € in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disclosure of operating segments [line items]
Segment capital expenditures	€ (71)	€ (50)	€ (130)	€ (97)
P&ARP [member]
Disclosure of operating segments [line items]
Segment capital expenditures	(23)	(17)	(44)	(30)
A&T [member]
Disclosure of operating segments [line items]
Segment capital expenditures	(16)	(10)	(29)	(23)
AS&I [member]
Disclosure of operating segments [line items]
Segment capital expenditures	(31)	(22)	(56)	(42)
Holdings & Corporate [member]
Disclosure of operating segments [line items]
Segment capital expenditures	€ (1)	€ (1)	€ (1)	€ (2)

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The cash outflow for the purchases of property, plant and equipment, classified as investing activities. [Refer: Property, plant and equipment]

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