Income Taxes (Components of Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current tax expense (benefit):
U.S.	$ 86	$ (346)	$ (47)
State and local	2	7	11
Foreign	879	681	594
Total current tax expense (benefit)	967	342	558
Deferred tax expense (benefit):
U.S.(1)	57	80	(2,552)
State and local	(1)	1	0
Foreign(1)	(76)	399	556
Total deferred tax expense (benefit)	(20)	480	(1,996)
Total income tax expense (benefit) on income (loss) before equity in earnings of operating joint ventures	947	822	(1,438)
Income tax expense (benefit) on equity in earnings of operating joint ventures	43	31	33
Income tax expense (benefit) on discontinued operations	0	0	0
Income tax expense (benefit) reported in equity related to:
Other comprehensive income (loss)	3,811	(1,812)	784
Stock-based compensation programs	0	0	(2)
Total income taxes	$ 4,801	$ (959)	$ (623)