Other Comprehensive Income (Loss) - Schedule of Changes in AOCI balance by Component (Details) - USD ($) $ in Millions	3 Months Ended								6 Months Ended	12 Months Ended
	Jun. 30, 2024		Mar. 31, 2024		Jun. 30, 2023	[2]	Mar. 31, 2023	[2]	Jun. 30, 2024	Dec. 31, 2023	Dec. 31, 2022
Other Comprehensive Income (Loss)
Income Before Reclassifications									$ 4
Amounts Reclassified to Net Earnings									8
Tax Expense									(3)
Total Other Comprehensive Income	$ 3	[1]	$ 6	[1]	$ (4)		$ 2		9	$ 131	$ (34)
Pension and Other Post-Employment Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2023, Net of Tax			(390)						(390)
Other Comprehensive Income (Loss)
Income Before Reclassifications									0
Amounts Reclassified to Net Earnings									6
Tax Expense									(2)
Total Other Comprehensive Income									4
Balance June 30, 2024, Net of Tax	(386)								(386)	(390)
Interest Rate Derivatives
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2023, Net of Tax			150						150
Other Comprehensive Income (Loss)
Income Before Reclassifications									4
Amounts Reclassified to Net Earnings									0
Tax Expense									(1)
Total Other Comprehensive Income									3
Balance June 30, 2024, Net of Tax	153								153	150
Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2023, Net of Tax			(39)						(39)
Other Comprehensive Income (Loss)
Income Before Reclassifications									0
Amounts Reclassified to Net Earnings									2
Tax Expense									0
Total Other Comprehensive Income									2
Balance June 30, 2024, Net of Tax	(37)								(37)	(39)
Accumulated Other Comprehensive (Loss) Income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2023, Net of Tax			(279)						(279)
Other Comprehensive Income (Loss)
Total Other Comprehensive Income	3	[1],[3]	$ 6	[1],[3]	$ (4)	[4]	$ 2	[4]		131	$ (34)
Balance June 30, 2024, Net of Tax	$ (270)								$ (270)	$ (279)

[1] See Note 11, Revision of Prior Period Financial Statements.

[2] See Note 11, Revision of Prior Period Financial Statements.

[3] Accumulated Other Comprehensive Loss balances shown above are net of tax. The associated taxes were $74 million as of December 31, 2023, $72 million as of March 31, 2024 and $72 million as of June 30, 2024. For additional information, see Note 10, Other Comprehensive Income.

[4] Accumulated Other Comprehensive Loss balances shown above are net of tax. The associated taxes were $129 million as of December 31, 2022, $128 million as of March 31, 2023 and $114 million as of June 30, 2023. For additional information, see Note 10, Other Comprehensive Income.