Risk management - Macroeconomic scenarios, sensitivity analysis and market risk - Additional information (Details) - EUR (€) € in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Disclosure Of Credit Risk Exposure [Line Items]
Global output percent	2.70%	5.90%
Expected global growth percent	2.50%
Global GDP increase	2.70%
Global GDP rate assumed	4.10%
Global GDP rate increase year two	2.50%
Global GDP rate increase assumed year two	3.10%
Economic sector based adjustments	€ 68	€ 341
Model time lag overlay	68	341
Payment Holiday, Management Adjustments	0	32
Mortgage portfolio - house price adjustments	131	124
Unweighted ECL for all collective provisioned clients in upside scenario	2,754
Unweighted ECL for all collective provisioned clients in baseline scenario	3,181
Unweighted ECL for all collective provisioned clients in down scenario	4,305
Reportable collective provisions	3,337
Total ECL collective-assessment for performing assets	1,849	1,003
Non-Derivative Financial Instruments To Transition To Alternative Benchmarks [Member]
Disclosure Of Credit Risk Exposure [Line Items]
Financial assets	40,485	42,570
Financial liabilities	1,501	1,565
Off balance sheet commitments	9,979	16,969
Non-Derivative Financial Instruments To Transition To Alternative Benchmarks [Member] \| USD LIBOR [Member]
Disclosure Of Credit Risk Exposure [Line Items]
Financial assets	40,485	41,805
Financial liabilities	1,501	1,542
Off balance sheet commitments	9,979	16,435
Derivative Financial Instruments Linked To USD LIBOR Have Yet To Transition [Member]
Disclosure Of Credit Risk Exposure [Line Items]
Financial assets	508,877	488,499
12-month expected credit losses [member]
Disclosure Of Credit Risk Exposure [Line Items]
Hypothetical collective-assessment ECLs	1,321	634
Lifetime expected credit losses [member]
Disclosure Of Credit Risk Exposure [Line Items]
Hypothetical collective-assessment ECLs	3,258	€ 2,232
Retail Banking [Member]
Disclosure Of Credit Risk Exposure [Line Items]
Second order impact overlay	40
Wholesale Banking [Member]
Disclosure Of Credit Risk Exposure [Line Items]
Second order impact overlay	€ 228

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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- Definition

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]

+ References

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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
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- Definition

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]]