Income Tax (Income Loss from Continuing Operations Before Income Tax Expense from Domestic and Foreign Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income (loss) from continuing operations:
U.S.	$ (803)	$ 684	$ 185
Non-U.S.	7,110	2,852	4,096
Income (loss) from continuing operations before provision for income tax	$ 6,307	$ 3,536	$ 4,281