RECLASSIFICATIONS OUT OF ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 19,646	$ 19,268	$ 19,196
Other-than-temporary impairment not recognized in earnings on securities	(17)	(22)	(22)
Net other comprehensive (loss) income	(281)	(15)	276
Ending balance	19,747	19,646	19,268
Net Unrealized (Losses) Gains on Derivatives
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	10	(69)	(298)
Other comprehensive income before reclassifications	(62)	93	212
Other-than-temporary impairment not recognized in earnings on securities	0	0	0
Amounts reclassified from other comprehensive income	(36)	(14)	17
Net other comprehensive (loss) income	(98)	79	229
Ending balance	(88)	10	(69)
Net Unrealized (Losses) Gains on Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(28)	74	(91)
Other comprehensive income before reclassifications	(139)	(66)	198
Other-than-temporary impairment not recognized in earnings on securities	(17)	(22)	(22)
Amounts reclassified from other comprehensive income	(2)	(14)	(11)
Net other comprehensive (loss) income	(158)	(102)	165
Ending balance	(186)	(28)	74
Employee Benefit Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(369)	(377)	(259)
Other comprehensive income before reclassifications	0	0	0
Other-than-temporary impairment not recognized in earnings on securities	0	0	0
Amounts reclassified from other comprehensive income	(25)	8	(118)
Net other comprehensive (loss) income	(25)	8	(118)
Ending balance	(394)	(369)	(377)
Total AOCI
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(387)	(372)	(648)
Other comprehensive income before reclassifications	(201)	27	410
Other-than-temporary impairment not recognized in earnings on securities	(17)	(22)	(22)
Amounts reclassified from other comprehensive income	(63)	(20)	(112)
Net other comprehensive (loss) income	(281)	(15)	276
Ending balance	$ (668)	$ (387)	$ (372)

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of other than temporary impairment loss (OTTI) on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss and attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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