For any sales of securities categorized as held-to-maturity, this item represents the net carrying amount of the sold security.

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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The cash inflow from securitizing loans held with the intention to resell in the near future.

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SECURITIES - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
SECURITIES - Narrative (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Impaired debt securities sold	$ 0	$ 0	$ 0	$ 0
Pretax non-credit related losses were deferred in OCI			29,000,000	41,000,000
Taxable interest income from securities	146,000,000	154,000,000	432,000,000	468,000,000
Available-for-sale Securities
Schedule of Available-for-sale Securities [Line Items]
Cumulative credit losses recognized in earnings	75,000,000	63,000,000	75,000,000	63,000,000	$ 75,000,000	$ 73,000,000	$ 66,000,000	$ 62,000,000	$ 62,000,000
Credit impairments recognized in earnings on securities that have been previously impaired	3,000,000	2,000,000	11,000,000	5,000,000	5,000,000
Reductions due to increases in cash flow expectations on impaired securities	(1,000,000)	(1,000,000)	(2,000,000)	(4,000,000)
Held-to-maturity Securities
Schedule of Available-for-sale Securities [Line Items]
Cumulative credit losses recognized in earnings	0	0	0	0	$ 0
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Securitizations of mortgage loans	$ 16,000,000	0	$ 21,000,000	0
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Value of held-to-maturity security sold		73,000,000		$ 73,000,000
Gain recognized on sale of held-to-maturity security		$ 2,000,000