Shareholders' Equity (Deficit) - Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ (742)	$ (429)
Other comprehensive income (loss) before reclassifications, net	(60)	53
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income	39	37
Tax expense	(10)	(11)
Amounts reclassified from accumulated other comprehensive income, net	29	26
Total other comprehensive income (loss)	(31)	79
Ending balance	(28)	58
AOCI Attributable to Parent
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(4,373)	(4,623)
Amounts reclassified from accumulated other comprehensive income
Ending balance	(4,404)	(4,544)
Change in Fair Value of Financial Instruments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	2	(11)
Other comprehensive income (loss) before reclassifications, net	72	0
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income	4	5
Tax expense	(1)	(2)
Amounts reclassified from accumulated other comprehensive income, net	3	3
Total other comprehensive income (loss)	75	3
Ending balance	77	(8)
Foreign Currency Translation Adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(1,584)	(1,861)
Other comprehensive income (loss) before reclassifications, net	(132)	54
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income	0	0
Tax expense	0	0
Amounts reclassified from accumulated other comprehensive income, net	0	0
Total other comprehensive income (loss)	(132)	54
Ending balance	(1,716)	(1,807)
Postretirement Benefit Obligation
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(2,791)	(2,751)
Other comprehensive income (loss) before reclassifications, net	0	(1)
Amounts reclassified from accumulated other comprehensive income
Amounts reclassified from accumulated other comprehensive income	35	32
Tax expense	(9)	(9)
Amounts reclassified from accumulated other comprehensive income, net	26	23
Total other comprehensive income (loss)	26	22
Ending balance	$ (2,765)	$ (2,729)