Accumulated Other Comprehensive Income (Loss) - After-tax Changes by Component (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (124)	$ (157)
Amounts arising during the period	1	0
Reclassifications from AOCI	0	5
Net OCI during the period	1	5
Balance at end of period	(123)	(152)
Unrealized gains (losses) on qualifying derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	3	1
Amounts arising during the period	0	0
Reclassifications from AOCI	1	1
Net OCI during the period	1	1
Balance at end of period	4	2
Defined benefit plans Prior service costs [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(5)	(6)
Amounts arising during the period	0	(1)
Reclassifications from AOCI	0	1
Net OCI during the period	0	0
Balance at end of period	(5)	(6)
Defined benefit plans Actuarial gain (loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(124)	(152)
Amounts arising during the period	0	0
Reclassifications from AOCI	(1)	3
Net OCI during the period	(1)	3
Balance at end of period	(125)	(149)
Equity Investees' OCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	2	0
Amounts arising during the period	1	1
Reclassifications from AOCI	0	0
Net OCI during the period	1	1
Balance at end of period	$ 3	$ 1