Consolidated Statements of Stockholders' Equity (USD $) In Millions	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock, at cost [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Beginning Balance at Dec. 31, 2011		$ 15	$ 3,826	$ 7,978	$ (4,113)	$ 8	$ 7,714
Beginning Balance (in shares) at Dec. 31, 2011		1,488
Net income				928			928
Other comprehensive income (loss), net of tax						290	290
Issuance of preferred stock	863						863
Dividends declared on preferred stock				(43)			(43)
Dividends declared on common stock				(308)			(308)
Stock option exercises and other			(40)		76		36
Stock-based compensation and related tax effects			98				98
Other	2		(3)	(1)	13		11
Ending Balance at Dec. 31, 2012	865	15	3,881	8,554	(4,024)	298	9,589
Ending Balance (in shares) at Dec. 31, 2012		1,488
Net income				1,071			1,071
Other comprehensive income (loss), net of tax						(289)	(289)
Dividends declared on preferred stock				(57)			(57)
Dividends declared on common stock				(311)			(311)
Stock option exercises and other			(54)		314		260
Stock-based compensation and related tax effects			119				119
Other	4		5	(4)	(6)		(1)
Ending Balance at Dec. 31, 2013	869	15	3,951	9,253	(3,716)	9	10,381
Ending Balance (in shares) at Dec. 31, 2013		1,488
Net income				1,321			1,321
Other comprehensive income (loss), net of tax						156	156
Dividends declared on preferred stock				(57)			(57)
Dividends declared on common stock				(316)			(316)
Stock option exercises and other			(53)		240		187
Stock-based compensation and related tax effects			139				139
Other	3		13	(3)	(21)		(8)
Ending Balance at Dec. 31, 2014	$ 872	$ 15	$ 4,050	$ 10,198	$ (3,497)	$ 165	$ 11,803
Ending Balance (in shares) at Dec. 31, 2014		1,488