Retirement Plans and Other Employee Benefits - Schedule of Benefit Obligation and Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pension Benefits
Change in benefit obligation
Benefit obligation, beginning of year	$ 675	$ 663
Interest cost	32	33	$ 20
Actuarial (gain) loss	(38)	20
Actual benefits paid	(42)	(41)
Premium paid for annuity purchase	(28)	0
Benefit obligation, end of year	599	675	663
Change in plan assets
Fair value of plan assets, beginning of year	638	641
Actual return on plan assets	7	35
Employer contributions	3	3
Actual benefits paid – settlement payments	(41)	(40)
Actual benefits paid – other payments	(1)	(1)
Premium paid for annuity purchase	(28)	0
Fair value of plan assets, end of year	578	638	641
Funded (unfunded) status of the plans	(21)	(37)
Amounts recognized in the Balance Sheets
Other assets	1	0
Other liabilities	(22)	(37)
Net asset (liability) at end of year	(21)	(37)
Other Benefits
Change in benefit obligation
Benefit obligation, beginning of year	31	32
Interest cost	2	2	1
Actuarial (gain) loss	(1)	0
Actual benefits paid	(2)	(3)
Premium paid for annuity purchase	0	0
Benefit obligation, end of year	30	31	32
Change in plan assets
Fair value of plan assets, beginning of year	23	21
Actual return on plan assets	2	2
Employer contributions	1	3
Actual benefits paid – settlement payments	(2)	(3)
Actual benefits paid – other payments	0	0
Premium paid for annuity purchase	0	0
Fair value of plan assets, end of year	24	23	$ 21
Funded (unfunded) status of the plans	(6)	(8)
Amounts recognized in the Balance Sheets
Other assets	22	21
Other liabilities	(28)	(29)
Net asset (liability) at end of year	$ (6)	$ (8)