Employee Benefits - Components of Net Periodic (Benefit) Cost (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Sep. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
U.K.
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0		$ 0		$ 0	$ 0
Interest cost	38		20		110	64
Expected return on plan assets, net of administration expenses	(49)		(32)		(143)	(102)
Amortization of prior-service cost	1		1		2	2
Amortization of net actuarial loss	19		7		56	22
Net periodic (benefit) cost	9		(4)		25	(14)
Loss on pension settlement	0		0		0	0
Total net periodic (benefit) cost	9		(4)		25	(14)
Other
Defined Benefit Plan Disclosure [Line Items]
Service cost	0		0		0	0
Interest cost	10		5		30	14
Expected return on plan assets, net of administration expenses	(12)		(8)		(36)	(25)
Amortization of prior-service cost	0		0		0	0
Amortization of net actuarial loss	3		3		10	10
Net periodic (benefit) cost	1				4	(1)
Loss on pension settlement	0	$ 27	0		27	0
Total net periodic (benefit) cost	1		0		31	(1)
U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	0		0		0	0
Interest cost	26		17		78	51
Expected return on plan assets, net of administration expenses	(29)		(27)		(89)	(81)
Amortization of prior-service cost	0		0		0	0
Amortization of net actuarial loss	8		17		25	50
Net periodic (benefit) cost	5		7		14	20
Loss on pension settlement	0		0	$ 1	0	1
Total net periodic (benefit) cost	$ 5		$ 7		$ 14	$ 21