Accumulated Other Comprehensive Loss - Changes in AOCL, After Tax and Minority Interest (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 4,837	$ 5,466
Ending balance	4,904	5,161
Foreign Currency Translation Adjustment
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(1,613)	(1,663)
Other comprehensive income (loss) before reclassifications	(24)	(12)
Amounts reclassified from accumulated other comprehensive loss	0	0
Ending balance	(1,637)	(1,675)
Unrealized Gains (Losses) from Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	1	1
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive loss	0	0
Ending balance	1	1
Unrecognized Net Actuarial Losses and Prior Service Costs
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(2,224)	(2,215)
Other comprehensive income (loss) before reclassifications	28	4
Amounts reclassified from accumulated other comprehensive loss	58	92
Ending balance	(2,138)	(2,119)
Deferred Derivative Gains (Losses)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	1	2
Other comprehensive income (loss) before reclassifications	0	(4)
Amounts reclassified from accumulated other comprehensive loss	1	1
Ending balance	2	(1)
Total
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(3,835)	(3,875)
Other comprehensive income (loss) before reclassifications	4	(12)
Amounts reclassified from accumulated other comprehensive loss	59	93
Ending balance	$ (3,772)	$ (3,794)