Retirement Plans and Other Employee Benefits - Schedule Of Components Of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 33	$ 20	$ 17
Expected return on plan assets	(32)	(24)	(20)
Actuarial (gain) loss	13	12	10
Net periodic benefit cost	14	8	7
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Interest cost	2	1	1
Expected return on plan assets	(1)	(2)	(1)
Actuarial (gain) loss	(1)	0	0
Net periodic benefit cost	$ 0	$ (1)	$ 0