Fair value of assets and liabilities - Methods applied in determining fair values of financial assets and liabilities (carried at amortised cost) (Details) - EUR (€) € in Millions	Jun. 30, 2022	Dec. 31, 2021	Dec. 31, 2020
Financial Assets
Loans and advances to banks	€ 22,966	€ 23,592
Loans and advances to customers	643,478	625,122
Financial Liabilities
Deposits from banks	90,513	85,092
Customer deposits	642,455	617,400
Debt securities in issue	93,123	91,784	€ 82,065
Subordinated loans	15,473	16,715	€ 15,805
Financial assets [member]
Financial Assets
Loans and advances to banks	22,845	23,635
Loans and advances to customers	619,738	635,657
Securities at amortised cost	45,601	48,323
Financial assets	688,184	707,614
Financial assets [member] \| Carrying amount [member]
Financial Assets
Loans and advances to banks	22,966	23,592
Loans and advances to customers	643,478	625,122
Securities at amortised cost	48,371	48,319
Financial assets	714,815	697,032
Financial liabilities [member]
Financial Liabilities
Deposits from banks	90,719	86,035
Customer deposits	641,837	617,641
Debt securities in issue	93,224	93,085
Subordinated loans	14,913	17,203
Financial liabilities	840,693	813,964
Financial liabilities [member] \| Carrying amount [member]
Financial Liabilities
Deposits from banks	90,513	85,092
Customer deposits	642,455	617,400
Debt securities in issue	93,123	91,784
Subordinated loans	15,473	16,715
Financial liabilities	€ 841,564	€ 810,990

The amount of instruments issued by the entity that represent indebtedness.

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The amount of deposit liabilities from banks held by the entity.

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The amount of deposit liabilities from customers held by the entity.

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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 amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) 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 deliver 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, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are 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. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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The amount of loans and advances the entity has made to banks.

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The amount of loans and advances the entity has made to customers.

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The amount of liabilities that are subordinate to other liabilities with respect to claims.

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The amount of securities at amortised cost.

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