Financial Risk Management and Financial Instruments - Summary of Liquidity Position in Terms of Available Cash and Cash Equivalents and Short Term Investments (Details) - EUR (€) € in Millions |
Dec. 31, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Disclosure Of Liquidity Risk [Line Items] | ||
| Short term investments | € 692 | € 915 |
| Liquidity Position | ||
| Disclosure Of Liquidity Risk [Line Items] | ||
| Short term investments | 692 | 915 |
| Short term deposits | 585 | 307 |
| Cash at bank and on hand | 480 | 584 |
| Total surplus liquidity | 1,757 | 1,806 |
| Liquidity position | € 1,757 | € 1,806 |