Retirement Plans and Other Employee Benefits - Schedule of Amounts Recognized in Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Benefits
Changes in plan assets and benefit obligation recognized in other comprehensive income
Net actuarial (gain) loss arising during measurement period	$ (13)	$ 17	$ 32
Items amortized during the measurement period:
Net actuarial gain (loss)	(13)	(13)	(11)
Total recognized in other comprehensive income	(26)	4	21
Other Benefits
Changes in plan assets and benefit obligation recognized in other comprehensive income
Net actuarial (gain) loss arising during measurement period	(2)	0	(3)
Items amortized during the measurement period:
Net actuarial gain (loss)	1	1	0
Total recognized in other comprehensive income	$ (1)	$ 1	$ (3)