Debt (Bilateral Credit Facilities) (Details) - Line of Credit	Sep. 30, 2020 EUR (€)	May 19, 2020 EUR (€)	Jan. 17, 2017 USD ($)
Revolving credit facility
Line of Credit Facility
Maximum borrowing capacity		€ 500,000,000	$ 2,500,000,000
Bilateral Credit Facility | Bilateral Credit Facility Expiring in May 2021
Line of Credit Facility
Maximum borrowing capacity | €	€ 100,000,000.0
JPMorgan Chase Bank [Member] | Letter of Credit [Member]
Line of Credit Facility
Maximum borrowing capacity | $			$ 1,500,000,000