Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits at beginning of year	$ 1,318	$ 1,375
Decrease in tax positions of prior periods netted against deferred tax assets	(411)	(661)
Decrease in tax positions taken in the current year	(73)
Increase in tax positions taken in the current year		634
Increase in tax positions taken in the prior year	752
Decrease in tax positions taken in the prior year		(3)
Decrease due to payments/settlements	(1)	0
Decrease from the lapse of statute of limitations	(52)	0
Decrease related to divestitures of businesses	(109)	(27)
Unrecognized tax benefits at end of year	$ 1,424	$ 1,318