Accumulated Other Comprehensive Income (Loss) - After-tax Changes by Component (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (163)	$ (124)
Amounts arising during the period	1	1
Reclassifications from AOCI	1	0
Net OCI during the period	2	1
Balance at end of period	(161)	(123)
Unrealized gains (losses) on qualifying derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	6	3
Amounts arising during the period	0	0
Reclassifications from AOCI	1	1
Net OCI during the period	1	1
Balance at end of period	7	4
Equity Investees' OCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	3	2
Amounts arising during the period	1	1
Reclassifications from AOCI	0	0
Net OCI during the period	1	1
Balance at end of period	4	3
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(168)	(124)
Amounts arising during the period	0	0
Reclassifications from AOCI	0	(1)
Net OCI during the period	0	(1)
Balance at end of period	(168)	(125)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(4)	(5)
Amounts arising during the period	0	0
Reclassifications from AOCI	0	0
Net OCI during the period	0	0
Balance at end of period	$ (4)	$ (5)