Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Common stock and paid-in capital [Member]	Preferred stock [Member]	Retained Earnings [Member]	Accumulated other comprehensive (loss) income [Member]	Treasury stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity Attributable to Parent, Total	$ 15,399	$ 21,038	$ 1,255	$ (6,828)		$ 0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(66)				$ (66)
Net Income (Loss) Attributable to Parent	1,289			1,289
Dividends, Preferred Stock, Cash	(2,571)			(2,571)
Stock Repurchased During Period, Value	(325)		(325)
Preferred Stock, Redemption Amount	(234)		(234)
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	62	62
Other Comprehensive Income (Loss), Net of Tax	(165)				(165)
Treasury Stock, Value, Acquired, Cost Method	(16)					(16)
Stock Repurchase and Redemption Premium	$ 2,364
Common Stock, Dividends, Per Share, Declared	$ 0.00
Stockholders' Equity Attributable to Parent, Total	$ 13,439	21,100	696	(8,110)		(16)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(231)				(231)
Net Income (Loss) Attributable to Parent	1,067			1,067
Dividends, Preferred Stock, Cash	(30)			(30)
Stock Repurchased During Period, Value	(696)		(696)
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	66	66
Other Comprehensive Income (Loss), Net of Tax	(110)				(110)
Treasury Stock, Value, Acquired, Cost Method	(341)					(341)
Dividends, Common Stock, Cash	$ (78)			(78)
Common Stock, Dividends, Per Share, Declared	$ 0.16
Stockholders' Equity Attributable to Parent, Total	$ 13,317	21,166	0	(7,151)		(357)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(341)				(341)
Net Income (Loss) Attributable to Parent	929			929
Dividends, Preferred Stock, Cash	0
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	79	79
Other Comprehensive Income (Loss), Net of Tax	106				106
Treasury Stock, Value, Acquired, Cost Method	(753)					(753)
Dividends, Common Stock, Cash	$ (184)			(184)
Common Stock, Dividends, Per Share, Declared	$ 0.40
Stockholders' Equity Attributable to Parent, Total	$ 13,494	$ 21,245	$ 0	$ (6,406)		$ (1,110)
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (235)				$ (235)