Equity - Reserves for Other Comprehensive Income (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Reserves within equity
Balance	€ 55,230	€ 44,519
Balance	53,644	55,230
Reserve for OCI on cash flow hedge derivatives
Reserves within equity
Balance	(342)	(896)
Changes of the year	73	(2,750)
Reversal to inventories adjustments	(5)	(6)
Reclassification adjustments	310	3,310
Balance	36	(342)
Reserve for OCI on cash flow hedge derivatives \| Gross reserve
Reserves within equity
Balance	(483)	(1,269)
Changes of the year	105	(3,883)
Reversal to inventories adjustments	(8)	(8)
Reclassification adjustments	436	4,677
Balance	50	(483)
Reserve for OCI on cash flow hedge derivatives \| Deferred tax liabilities, gross
Reserves within equity
Balance	141	373
Changes of the year	(32)	1,133
Reversal to inventories adjustments	3	2
Reclassification adjustments	(126)	(1,367)
Balance	(14)	141
Reserve for OCI on defined benefit plans
Reserves within equity
Balance	(58)	(117)
Changes of the year	(21)	55
Currency translation differences	(9)	1
Changes in scope of consolidation		3
Balance	(88)	(58)
OCI relating to equity-accounted investments	1	1
Reserve for OCI on defined benefit plans \| Gross reserve
Reserves within equity
Balance	(20)	(84)
Changes of the year	(31)	60
Currency translation differences	(43)	1
Changes in scope of consolidation		3
Balance	(94)	(20)
Reserve for OCI on defined benefit plans \| Deferred tax liabilities, gross
Reserves within equity
Balance	(38)	(33)
Changes of the year	10	(5)
Currency translation differences	34
Balance	6	(38)
Reserve for OCI on equity-accounted investments
Reserves within equity
Balance	46	54
Changes of the year	52	92
Changes in scope of consolidation		1
Reclassification adjustments		(101)
Balance	98	46
Reserve for OCI on Investments fair value
Reserves within equity
Balance	53	141
Changes of the year	45	56
Reclassification to retained earnings		(144)
Balance	€ 98	€ 53

The amount of increase (decrease) in reserves within equity resulting from the changes in scope of consolidation.

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The increase (decrease) in equity resulting from reclassification to retained earnings.

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No definition available.

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Represents the reclassification adjustments in equity reserve for during the year.

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Represents the changes in equity during the period.

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Represents the equity reserve for financial assets.

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The amount of reversal to inventories adjustments.

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The amount of share of accumulated other comprehensive income of equity-accounted investments.

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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.

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The amount of residual interest in the assets of the entity after deducting all its liabilities.

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