Tax Matters - Reconciliation of Profit (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Abstract]
Accounting profit before tax	€ 2,960	€ 12,095	€ 2,583
Tax expense at prevailing statutory rate	797	2,768	532
Permanent differences	(793)	(1,705)	289
Changes in deferred tax charge due to changes in tax rates	1	51	14
(Capitalization)/reversal of tax deduction and tax relief	88	225	(103)
(Capitalization)/reversal of loss carryforwards	197	(307)	(88)
Increase/(decrease) in tax expense arising from temporary differences	43	84	(8)
Other concepts	308	262	(10)
Current tax expense	(218)	831	462
Deferred tax expense	859	547	164
Corporate income tax	€ 641	€ 1,378	€ 626

The amount of profit (loss) for a period before deducting tax expense. [Refer: Profit (loss)]

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The amount of income taxes payable (recoverable) in respect of the taxable profit (tax loss) for a period.

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The amount of tax expense (income) relating to changes in deferred tax liabilities and deferred tax assets. [Refer: Deferred tax assets; Deferred tax liabilities]

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The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that the entity does not separately disclose in the same statement or note. [Refer: Accounting profit; Applicable tax rate]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that relates to changes in the tax rate. [Refer: Accounting profit]

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The product of the accounting profit multiplied by the applicable tax rate(s). [Refer: Accounting profit; Applicable tax rate]

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Income Taxes [Abstract]

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Increase (Decrease) In Tax Expense Due To Temporary Differences

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Reversal (Capitalization) Of Loss Carryforwards

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Reversal (Capitalization) Of Tax Deduction And Tax Relief

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Tax Effect Of Other Permanent Differences

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