CONSOLIDATED STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Balance at beginning of period at Dec. 31, 2013		$ 1,565
Balance at beginning of period at Dec. 31, 2013			$ 0	$ 14,106	$ 952	$ (159)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred stock redemption		0
Capital contribution from parent				0
Employee benefit plans				0
Net income	$ 283				283
Cash dividends declared on preferred stock					(36)
Other comprehensive income (loss), net of tax	273					273
Balance at end of period at Jun. 30, 2014	15,419		0	14,106	1,199	114
Balance at end of period at Jun. 30, 2014	16,984	1,565
Balance at beginning of period at Dec. 31, 2014	16,967	1,565
Balance at beginning of period at Dec. 31, 2014	15,402		0	14,170	1,233	(1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred stock redemption		(300)
Capital contribution from parent				4,000
Employee benefit plans				(1)
Net income	251				251
Cash dividends declared on preferred stock					(36)
Other comprehensive income (loss), net of tax	(228)					(228)
Balance at end of period at Jun. 30, 2015	19,388		$ 0	$ 18,169	$ 1,448	$ (229)
Balance at end of period at Jun. 30, 2015	$ 20,653	$ 1,265