Segment information - Summary of Revenue by Geographic Area (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disclosure of operating segments [line items]
Revenue	€ 7,880	€ 6,764	€ 5,259
United States
Disclosure of operating segments [line items]
Revenue	2,947	2,542	1,973
United Kingdom
Disclosure of operating segments [line items]
Revenue	836	727	576
Luxembourg
Disclosure of operating segments [line items]
Revenue	5	4	3
Other Countries
Disclosure of operating segments [line items]
Revenue	€ 4,092	€ 3,491	€ 2,707

The income arising in the course of an entity's ordinary activities. Income is increases in assets, or decreases in liabilities, that result in increases in equity, other than those relating to contributions from holders of equity claims.

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+ Details