CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY(UNAUDITED) - 9 months ended Sep. 30, 2015 - USD ($) $ in Millions	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Beginning balance at Dec. 31, 2014	$ 45,053	$ 0	$ 6	$ 27,869	$ 23,973	$ (430)	$ (6,365)
Beginning balance (shares) at Dec. 31, 2014		1,875,000	643,557,048
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income	3,418				3,130	288
Common Stock Dividends, Shares			40,955
Dividends, Common Stock	(602)		$ 0	4	(606)
Cash dividends - preferred series	(90)				(90)
Purchases of treasury stock	(1,815)						(1,815)
Issuances of common stock and restricted stock, shares, net of forfeitures			2,180,098
Issuances of common stock and restricted stock, value, net of forfeitures	84		$ 0	84
Exercise of stock options and warrants, tax effects of exercises and restricted stock vesting, shares			2,089,451
Exercise of stock options and warrants, tax effects of exercises and restricted stock vesting, value	70		$ 0	70
Stock Issued During Period, Shares, New Issues		1,500,000
Stock Issued During Period, Value, New Issues	1,472	$ 0		1,472
Compensation expense for restricted stock awards and stock options	95			95
Ending balance at Sep. 30, 2015	$ 47,685	$ 0	$ 6	$ 29,594	$ 26,407	$ (142)	$ (8,180)
Ending balance (shares) at Sep. 30, 2015		3,375,000	647,867,552