Other disclosures - Spain Real Estate Business: gross, collateral, allowance (Details) - Spain € in Millions	Jun. 30, 2020 EUR (€)
Accumulated impairment
Distribution of portfolio
Financial assets	€ 1,727
Construction and property development
Distribution of portfolio
Financial assets	2,936
Construction and property development \| Gross carrying amount
Distribution of portfolio
Financial assets	3,031
Written-off assets	924
Construction and property development \| Gross carrying amount \| Nonperforming
Distribution of portfolio
Financial assets	238
Construction and property development \| Excess over collateral value
Distribution of portfolio
Excess over collateral value	374
Written-off assets
Construction and property development \| Excess over collateral value \| Nonperforming
Distribution of portfolio
Excess over collateral value	25
Construction and property development \| Accumulated impairment
Distribution of portfolio
Financial assets	(95)
Written-off assets
Construction and property development \| Accumulated impairment \| Nonperforming
Distribution of portfolio
Financial assets	€ (81)

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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