v3.25.4
Employee Benefits - Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) (Detail)
€ in Millions
 12 Months Ended
Dec. 31, 2025
EUR (€)
yr
Actual benefit payments 2025  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans € 824
Actual benefit payments 2025 | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 554
Actual benefit payments 2025 | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 109
Actual benefit payments 2025 | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 89
Actual benefit payments 2025 | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 72
Within 1 year  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 861
Within 1 year | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 580
Within 1 year | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 131
Within 1 year | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 78
Within 1 year | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 72
Later than one year and not later than two years  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 870
Later than one year and not later than two years | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 582
Later than one year and not later than two years | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 139
Later than one year and not later than two years | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 77
Later than one year and not later than two years | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 72
Later than two years and not later than three years  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 902
Later than two years and not later than three years | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 601
Later than two years and not later than three years | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 148
Later than two years and not later than three years | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 83
Later than two years and not later than three years | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 70
Later than three years and not later than four years  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 932
Later than three years and not later than four years | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 616
Later than three years and not later than four years | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 160
Later than three years and not later than four years | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 84
Later than three years and not later than four years | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 72
Later than four years and not later than five years  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 946
Later than four years and not later than five years | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 630
Later than four years and not later than five years | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 165
Later than four years and not later than five years | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 81
Later than four years and not later than five years | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 70
Later than five years and not later than ten years  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 4,922
Later than five years and not later than ten years | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 3,221
Later than five years and not later than ten years | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 891
Later than five years and not later than ten years | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans 418
Later than five years and not later than ten years | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Benefits Expected to be paid by the Retirement Benefit Plans € 392
Weighted average duration of defined benefit
obligation (in years)  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Weighted average duration of defined benefit
obligation (in years) | yr 10
Weighted average duration of defined benefit
obligation (in years) | Germany  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Weighted average duration of defined benefit
obligation (in years) | yr 10
Weighted average duration of defined benefit
obligation (in years) | U.K.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Weighted average duration of defined benefit
obligation (in years) | yr 12
Weighted average duration of defined benefit
obligation (in years) | U.S.  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Weighted average duration of defined benefit
obligation (in years) | yr 9
Weighted average duration of defined benefit
obligation (in years) | Other  
Benefits Expected to be paid by the Retirement Benefit Plans (Impact on Cashflows) [Line Items]  
Weighted average duration of defined benefit
obligation (in years) | yr 9