Investments in associates and joint ventures - Summary of changes in investments in associates and joint ventures (Details) - EUR (€) € in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Opening balance	€ 1,587
Share of results	35	€ 23	€ 141
Closing balance	1,477		1,587
Associates and joint ventures [member]
Disclosure of Investments in Associates and Joint Ventures [Line Items]
Opening balance	1,587	€ 1,475	1,475
Additions	16		91
Revaluations	(6)		(24)
Share of results	35		141
Dividends received	(31)		(34)
Disposals	(6)		(23)
Impairments	(153)		(3)
Exchange rate differences	29		(31)
Other	4		(5)
Closing balance	€ 1,477		€ 1,587

The increase (decrease) in financial assets resulting from foreign exchange. [Refer: Financial assets]

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The amount of investments in subsidiaries, joint ventures and associates in an entity's separate financial statements. [Refer: Associates [member]; Joint ventures [member]; Subsidiaries [member]; Investments in subsidiaries reported in separate financial statements]

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The entity's share of the profit (loss) of associates and joint ventures accounted for using the equity method. [Refer: Associates [member]; Investments accounted for using equity method; Joint ventures [member]; Profit (loss)]

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Additions in investments in associates and joint ventures.

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Disclosure of investments in associates and joint ventures.

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The amount of other changes in investments accounted for using equity method.

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