Leases - Lease activity (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating lease expense included in other expenses	$ 36	$ 36	$ 41
Sublease income	0	(2)	(2)
Total lease expense, net of sublease income	$ 36	$ 34	$ 39