Segment Information - Summary of Additional Information by Geographies (Parenthetical) (Detail) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Additional information by geographies [Line Items]
Revenue	€ 50,724	€ 51,980	€ 50,982
North America [Member]
Additional information by geographies [Line Items]
Revenue	10,117	9,411	9,041
Latin America [Member]
Additional information by geographies [Line Items]
Revenue	€ 5,963	€ 7,071	€ 6,979

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