Other Comprehensive Income (Loss) - Changes in AOCI Balance by Component (Details) - USD ($) $ in Millions	3 Months Ended										9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022		Mar. 31, 2022		Sep. 30, 2021	Jun. 30, 2021		Mar. 31, 2021		Sep. 30, 2022
Other Comprehensive Income (Loss)
Income Before Reclassifications											$ 82
Amounts Reclassified to Net Earnings											27
Tax (Expense)/Benefit											(21)
Total Other Comprehensive Income	$ 18	$ 39		$ 31		$ 17	$ (21)		$ 68		88
Pension and Other Post-Employment Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2021, Net of Tax				(431)							(431)
Other Comprehensive Income (Loss)
Income Before Reclassifications											0
Amounts Reclassified to Net Earnings											32
Tax (Expense)/Benefit											(7)
Total Other Comprehensive Income											25
Balance September 30, 2022, Net of Tax	(406)										(406)
Interest Rate Derivatives
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2021, Net of Tax				70							70
Other Comprehensive Income (Loss)
Income Before Reclassifications											82
Amounts Reclassified to Net Earnings											0
Tax (Expense)/Benefit											(19)
Total Other Comprehensive Income											63
Balance September 30, 2022, Net of Tax	133										133
Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2021, Net of Tax				(47)							(47)
Other Comprehensive Income (Loss)
Income Before Reclassifications											0
Amounts Reclassified to Net Earnings											(5)
Tax (Expense)/Benefit											5
Total Other Comprehensive Income											0
Balance September 30, 2022, Net of Tax	(47)										(47)
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance December 31, 2021, Net of Tax				(408)							(408)
Other Comprehensive Income (Loss)
Total Other Comprehensive Income	18	$ 39	[1]	$ 31	[1]	$ 17	$ (21)	[2]	$ 68	[2]
Balance September 30, 2022, Net of Tax	$ (320)										$ (320)

[1] Accumulated Other Comprehensive Loss balances shown above are net of tax. The associated taxes were $107 million as of December 31, 2021; $99 million as of March 31, 2022; $88 million as of June 30, 2022; and $85 million as of September 30, 2022. For additional information, see Note 10, Other Comprehensive Income.

[2] Accumulated Other Comprehensive Loss balances shown above are net of tax. The associated taxes were $156 million as of December 31, 2020; $137 million as of March 31, 2021; $142 million as of June 30, 2021; and $136 million as of September 30, 2021. For additional information, see Note 10, Other Comprehensive Income.