Provisions, income tax liabilities and other liabilities - Expected Timing of Benefit Payments under Pension and Other Post-employment Benefit Plans (Details) € in Millions	Dec. 31, 2024 EUR (€)
Year 1
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	€ 565
Year 2
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	538
Year 3
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	553
Year 4
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	566
Year 5
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	584
2030 to 2034
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	2,959
France \| Year 1
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	94
France \| Year 2
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	59
France \| Year 3
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	71
France \| Year 4
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	75
France \| Year 5
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	81
France \| 2030 to 2034
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	497
Germany \| Year 1
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	210
Germany \| Year 2
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	210
Germany \| Year 3
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	208
Germany \| Year 4
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	207
Germany \| Year 5
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	209
Germany \| 2030 to 2034
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	893
US \| Year 1
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	97
US \| Year 2
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	98
US \| Year 3
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	100
US \| Year 4
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	103
US \| Year 5
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	107
US \| 2030 to 2034
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	543
UK \| Year 1
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	126
UK \| Year 2
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	130
UK \| Year 3
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	134
UK \| Year 4
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	139
UK \| Year 5
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	143
UK \| 2030 to 2034
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	785
Other \| Year 1
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	38
Other \| Year 2
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	41
Other \| Year 3
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	40
Other \| Year 4
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	42
Other \| Year 5
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	44
Other \| 2030 to 2034
Disclosure of defined benefit plans [line items]
Estimated future benefit payments under pension and other post-employment benefit plans	€ 241

Provisions, income tax liabilities and other liabilities - Expected Timing of Benefit Payments under Pension and Other Post-employment Benefit Plans (Details)
€ in Millions