Financial assets - Impaired assets (Details) - Financial assets at amortised cost, category - EUR (€) € in Millions	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Disclosure of reconciliation of changes in loss allowance of financial instruments
Written-off assets	€ (5,183)	€ (6,246)
Exchange differences and other	1,716	(434)
Gross carrying amount \| Financial instruments credit-impaired
Disclosure of reconciliation of changes in loss allowance of financial instruments
Financial assets at beginning of period	33,184	35,091
Additions	5,586	4,581
Written-off assets	(5,183)	(6,246)
Exchange differences and other	(1,407)	343
Financial assets at end of period	€ 32,180	€ 33,769

The decrease in financial assets resulting from write-off. [Refer: Financial assets]

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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

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