SECURITIES - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Credit impairments recognized in earnings	$ 2,000,000	$ 2,000,000	$ 3,000,000	$ 6,000,000
Impaired debt securities sold			0	0
Pretax non-credit related losses were deferred in OCI			29,000,000	33,000,000
Available-for-sale Securities
Schedule of Available-for-sale Securities [Line Items]
Cumulative balance at end of period	62,000,000	60,000,000	62,000,000	60,000,000	$ 62,000,000	$ 62,000,000	$ 59,000,000	$ 56,000,000
Credit impairments recognized in earnings	2,000,000	2,000,000	3,000,000	6,000,000
Reductions due to increases in cash flow expectations on impaired securities	2,000,000	1,000,000	3,000,000	2,000,000
Held-to-maturity Securities
Schedule of Available-for-sale Securities [Line Items]
Cumulative balance at end of period	$ 0	$ 0	$ 0	$ 0