Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Millions		Total		Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock and Other	[1]	AOCI Attributable to Parent [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding					509,000
Total shareholders' equity at Dec. 31, 2015		$ 23,437		$ 1,225	$ 550	$ 9,094	$ 14,686	$ (1,658)		$ (460)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative effect of credit risk adjustment	[2]	0					5			(5)	[3]
Net Income (Loss) Attributable to Parent		447					447
Other Comprehensive Income (Loss), Net of Tax		486								486
Noncontrolling Interest, Period Increase (Decrease)		(7)						(7)
Dividends, Common Stock, Cash		(121)					(121)
Dividends, Preferred Stock, Cash	[4]	(17)					(17)
Treasury Stock, Shares, Acquired					(4,000)
Treasury Stock, Value, Acquired, Cost Method		(151)						(151)
Payments for Repurchase of Warrants		(24)				(24)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period					0
Stock Issued During Period, Value, Stock Options Exercised		(1)				(3)		(2)
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures					0
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures		2				(50)	(1)	53
Adjustments to Additional Paid in Capital, Share-based Compensation, Restricted Stock Unit or Restricted Stock Award, Requisite Service Period Recognition		2						2
Total shareholders' equity at Mar. 31, 2016		$ 24,053		1,225	$ 550	9,017	14,999	(1,759)		21
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding					505,000
Common Stock, Shares, Outstanding		491,188	[5]		491,000
Total shareholders' equity at Dec. 31, 2016		$ 23,618		1,225	$ 550	9,010	16,000	(2,346)		(821)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss) Attributable to Parent		468					468
Other Comprehensive Income (Loss), Net of Tax		(46)								(46)
Noncontrolling Interest, Period Increase (Decrease)		(2)						(2)
Dividends, Common Stock, Cash		(128)					(128)
Dividends, Preferred Stock, Cash	[4]	(17)					(17)
Treasury Stock, Shares, Acquired					(7,000)
Treasury Stock, Value, Acquired, Cost Method		(414)						(414)
Payments for Repurchase of Warrants		0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period					1,000
Stock Issued During Period, Value, Stock Options Exercised		(9)				(12)		(21)
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures					1,000
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures		(4)				(32)	(1)	29
Total shareholders' equity at Mar. 31, 2017		$ 23,484		$ 1,225	$ 550	$ 8,966	$ 16,322	$ (2,712)		$ (867)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding		485,712	[5]		486,000

[1] At March 31, 2017, includes ($2,812) million for treasury stock, ($1) million for the compensation element of restricted stock, and $101 million for noncontrolling interest.At March 31, 2016, includes ($1,859) million for treasury stock, ($1) million for the compensation element of restricted stock, and $101 million for noncontrolling interest.

[2] Related to the Company's early adoption of the ASU 2016-01 provision related to changes in instrument-specific credit risk, beginning January 1, 2016. See Note 1, "Significant Accounting Policies," and Note 18, "Accumulated Other Comprehensive (Loss)/Income," for additional information.

[3] Related to the Company's early adoption of the ASU 2016-01 provision related to changes in instrument-specific credit risk. See Note 1, "Significant Accounting Policies," for additional information.

[4] For the three months ended March 31, 2017, dividends were $1,000 per share for both Perpetual Preferred Stock Series A and B, $1,469 per share for Perpetual Preferred Stock Series E, and $1,406 per share for Perpetual Preferred Stock Series F.For the three months ended March 31, 2016, dividends were $1,011 per share for both Perpetual Preferred Stock Series A and B, $1,469 per share for Perpetual Preferred Stock Series E, and $1,406 per share for Perpetual Preferred Stock Series F.

[5] Includes restricted shares of 11 thousand and 11 thousand at March 31, 2017 and December 31, 2016, respectively.