Income Taxes, Change in Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Unrecognized Tax Benefits [Roll Forward]
Balance as of beginning of year	$ 284	$ 816	$ 847
Additions for tax positions related to the current year	18	27	3
Additions for tax positions related to prior years	4	19	13
Reductions for tax positions related to prior years	(73)	(573)	(25)
Reductions for tax positions related to the lapse of applicable statute of limitations	(9)	(5)	0
Settlements	(38)	0	(22)
Balance as of end of year	$ 186	$ 284	$ 816