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Borrowings - Summary of Composition of Carrying Amounts of Total Borrowings (Detail) - EUR (€) € in Millions	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018	Dec. 31, 2017
Disclosure of detailed information about borrowings [line items]
Total borrowings	€ 2,378	€ 2,253	€ 2,151	€ 2,127
U.S. Dollar [member]
Disclosure of detailed information about borrowings [line items]
Total borrowings	1,541		1,408
Euro [member]
Disclosure of detailed information about borrowings [line items]
Total borrowings	811		726
Other currencies [member]
Disclosure of detailed information about borrowings [line items]
Total borrowings	€ 26		€ 17

X

- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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