RECLASSIFICATIONS OUT OF ACCUMULATED OTHER COMPREHENSIVE INCOME - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			$ (372)	$ (648)
Other comprehensive income (loss) before reclassifications			40	308
Other-than-temporary impairment not recognized in earnings on securities	$ 1	$ (2)	(18)	(21)
Amounts reclassified from other comprehensive income (loss)			(9)	3
Net other comprehensive (loss) income			13	290
Ending balance	(359)	(358)	(359)	(358)
Net Unrealized Gains (Losses) on Derivatives
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			(69)	(298)
Other comprehensive income (loss) before reclassifications			60	120
Other-than-temporary impairment not recognized in earnings on securities			0	0
Amounts reclassified from other comprehensive income (loss)			(4)	13
Net other comprehensive (loss) income			56	133
Ending balance	(13)	(165)	(13)	(165)
Net Unrealized Gains (Losses) on Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			74	(91)
Other comprehensive income (loss) before reclassifications			(20)	188
Other-than-temporary impairment not recognized in earnings on securities			(18)	(21)
Amounts reclassified from other comprehensive income (loss)			(9)	(12)
Net other comprehensive (loss) income			(47)	155
Ending balance	27	64	27	64
Defined Benefit Pension Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance			(377)	(259)
Other comprehensive income (loss) before reclassifications			0	0
Other-than-temporary impairment not recognized in earnings on securities			0	0
Amounts reclassified from other comprehensive income (loss)			4	2
Net other comprehensive (loss) income			4	2
Ending balance	$ (373)	$ (257)	$ (373)	$ (257)