Shareholders' Equity - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2023	Mar. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance		$ (9,550)
Other comprehensive income (loss) before reclassifications	[1]	27	$ 118
Amounts reclassified from AOCI	[1]	(27)	171
Net current period Other comprehensive income/(loss)	[1]	0	289
Ending balance		(9,550)
Amortization of actuarial losses		(2)	159
Amortization of actuarial loss included in net periodic pension cost, tax		0	(40)
Loss on discontinuation of cash flow hedge due to forecasted transaction probable of not occurring, net			39
Loss on discontinuation of cash flow hedge due to forecasted transaction Probable of not occurring, tax			11
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	[1]	(9,550)	(11,659)
Ending balance	[1]	(9,550)	(11,370)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance		(167)	(105)
Other comprehensive income (loss) before reclassifications		16	24
Net current period Other comprehensive income/(loss)		16	24
Ending balance		(151)	(81)
Unrealized Gains and Losses on Certain Investments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			1
Other comprehensive income (loss) before reclassifications
Net current period Other comprehensive income/(loss)
Ending balance			1
Unrealized Gains and Losses on Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance		(24)	6
Other comprehensive income (loss) before reclassifications		18	94
Amounts reclassified from AOCI		(5)	35
Net current period Other comprehensive income/(loss)		13	129
Ending balance		(11)	135
Defined Benefit Pension Plans & Other Postretirement Benefits
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance		(9,359)	(11,561)
Other comprehensive income (loss) before reclassifications		(7)
Amounts reclassified from AOCI		(22)	136
Net current period Other comprehensive income/(loss)		(29)	136
Ending balance		$ (9,388)	$ (11,425)

[1] Net of tax.