Other Comprehensive Income (Loss) - Changes in AOCI Balance by Component (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2023	Mar. 31, 2022
Other Comprehensive Income (Loss)
Income Before Reclassifications		$ (3)
Amounts Reclassified to Net Earnings		6
Tax (Expense)/Benefit		(1)
Total Other Comprehensive Income		2	$ 31
Pension and Other Post-Employment Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2022, Net of Tax		(497)
Other Comprehensive Income (Loss)
Income Before Reclassifications		0
Amounts Reclassified to Net Earnings		4
Tax (Expense)/Benefit		(1)
Total Other Comprehensive Income		3
Balance March 31, 2023, Net of Tax		(494)
Interest Rate Derivatives
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2022, Net of Tax		150
Other Comprehensive Income (Loss)
Income Before Reclassifications		(3)
Amounts Reclassified to Net Earnings		0
Tax (Expense)/Benefit		0
Total Other Comprehensive Income		(3)
Balance March 31, 2023, Net of Tax		147
Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2022, Net of Tax		(41)
Other Comprehensive Income (Loss)
Income Before Reclassifications		0
Amounts Reclassified to Net Earnings		2
Tax (Expense)/Benefit		0
Total Other Comprehensive Income		2
Balance March 31, 2023, Net of Tax		(39)
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2022, Net of Tax		(388)
Other Comprehensive Income (Loss)
Total Other Comprehensive Income	[1]	2	$ 31
Balance March 31, 2023, Net of Tax		$ (386)

[1] Accumulated Other Comprehensive Loss balances shown above are net of tax. The associated taxes were $121 million and $99 million as of March 31, 2023, and March 31, 2022, respectively. For additional information, see Note 10, Other Comprehensive Income.