Employee Benefits - Amounts Recognized in the Consolidated Statements of Financial Position (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Prepaid benefit cost	$ 603	$ 556
Pension Plan | U.K.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Prepaid benefit cost	521	505
Accrued benefit liability - current	(1)	(1)
Accrued benefit liability - non-current	(11)	(26)
Accumulated other comprehensive loss	1,941	1,897
Net amount recognized	2,450	2,375
Pension Plan | Other
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Prepaid benefit cost	0	0
Accrued benefit liability - current	(4)	(4)
Accrued benefit liability - non-current	(50)	(51)
Accumulated other comprehensive loss	467	414
Net amount recognized	413	359
Pension Plan | U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Prepaid benefit cost	0	0
Accrued benefit liability - current	(43)	(42)
Accrued benefit liability - non-current	(536)	(573)
Accumulated other comprehensive loss	1,304	1,276
Net amount recognized	$ 725	$ 661