Consolidated Statements of Shareholders' Equity (Parenthetical) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Treasury Stock, Value	[1]	$ (4,178)		$ (3,591)
Common stock dividends, per share		$ 0.80	$ 0.52
Treasury Stock and Other
Treasury Stock, Value		$ (4,281)	$ (3,048)
Deferred Compensation Equity		0	0
Stockholders' Equity Attributable to Noncontrolling Interest		$ 103	$ 103	$ 103
Series A Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		$ 2,022	$ 2,022
Series B Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		2,022	2,022
Series E Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		1,469	2,938
Series F Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		2,813	2,813
Series G Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		2,525	$ 828
Series H Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		$ 3,004

[1] Includes noncontrolling interest of $103 million and $103 million at June 30, 2018 and December 31, 2017, respectively.