Consolidated Statements of Shareholders' Equity (Parenthetical) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Treasury Stock, Value	[1]	$ (3,853)
Common stock dividends, per share		$ 0.40	$ 0.26
Treasury Stock and Other
Treasury Stock, Value		$ (3,953)	$ (2,812)
Deferred Compensation Equity		(1)	(1)
Stockholders' Equity Attributable to Noncontrolling Interest		$ 101	$ 101
Series A Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		$ 1,000	$ 1,000
Series B Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		1,000	1,000
Series E Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		1,469	1,469
Series F Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		1,406	$ 1,406
Series G Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		1,038
Series H Preferred Stock [Member]
Preferred Stock, Dividends, Per Share, Cash Paid		$ 1,281

[1] Includes noncontrolling interest of $101 million and $103 million at March 31, 2018 and December 31, 2017, respectively.