Fair value measurement - Disclosure of assets and liabilities not measured at fair value on a recurring basis (Details) - EUR (€) € in Millions	Dec. 31, 2025	Dec. 31, 2024
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets	€ 3,781	€ 7,166
Not measured at fair value in statement of financial position \| Total Debt, excluding Lease liabilities
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial liabilities	43,493	34,671
Financial liabilities, at fair value	42,852	33,878
Not measured at fair value in statement of financial position \| Asset-backed financing
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial liabilities	15,479	10,016
Financial liabilities, at fair value	15,331	10,037
Not measured at fair value in statement of financial position \| Notes
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial liabilities	23,201	19,117
Financial liabilities, at fair value	22,698	18,302
Not measured at fair value in statement of financial position \| Borrowings from banks & Other debt
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial liabilities	4,813	5,538
Financial liabilities, at fair value	4,823	5,539
Not measured at fair value in statement of financial position \| Receivables from financing activities
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets	15,728	12,531
Financial assets, at fair value	15,073	12,008
Not measured at fair value in statement of financial position \| Dealer financing
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets	3,084	2,330
Financial assets, at fair value	3,095	2,329
Not measured at fair value in statement of financial position \| Retail financing
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets	10,703	8,494
Financial assets, at fair value	10,096	7,855
Not measured at fair value in statement of financial position \| Finance lease
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets	540	299
Financial assets, at fair value	522	325
Not measured at fair value in statement of financial position \| Other receivables from financing activities
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]
Financial assets	1,401	1,408
Financial assets, at fair value	€ 1,360	€ 1,499

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: Classes of financial instruments [domain]; Financial liabilities]

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The fair value of financial assets. [Refer: At fair value [member]; Financial assets]

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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: Classes of financial instruments [domain]; Financial assets; Derivatives [member]]

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