Commitments and Contingencies - Schedule of Future Minimum Lease Payments Under Non-cancellable Operating Leases (Details) - EUR (€) |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|---|
| Disclosure Of Finance Lease And Operating Lease By Lessee [Line Items] | |||
| Minimum lease payments under non-cancellable operating leases | € 833,000,000 | € 769,000,000 | € 212,000,000 |
| Not Later Than One Year | |||
| Disclosure Of Finance Lease And Operating Lease By Lessee [Line Items] | |||
| Minimum lease payments under non-cancellable operating leases | 62,000,000 | 47,000,000 | 25,000,000 |
| Later Than One Year But Not More Than 5 Years | |||
| Disclosure Of Finance Lease And Operating Lease By Lessee [Line Items] | |||
| Minimum lease payments under non-cancellable operating leases | 288,000,000 | 244,000,000 | 97,000,000 |
| Later Than Five Years | |||
| Disclosure Of Finance Lease And Operating Lease By Lessee [Line Items] | |||
| Minimum lease payments under non-cancellable operating leases | € 483,000,000 | € 478,000,000 | € 90,000,000 |