INVESTMENT SECURITIES (Details 3) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014 item	Dec. 31, 2013 item
INVESTMENT SECURITIES.
Number of investment securities in an unrealized loss position	195	321
Total temporary impaired securities
Less than 12 months, Fair Value	$ 187,596	$ 1,252,120
Less than 12 months, Unrealized Losses	(891)	(44,428)
12 months or longer, Fair Value	520,087	37,595
12 months or longer, Unrealized Losses	(8,869)	(3,680)
Total, Fair Value	707,683	1,289,715
Total, Unrealized Losses	(9,760)	(48,108)
States and political subdivisions debt securities
Total temporary impaired securities
Less than 12 months, Fair Value	23,591	137,176
Less than 12 months, Unrealized Losses	(145)	(8,985)
12 months or longer, Fair Value	68,622	32,747
12 months or longer, Unrealized Losses	(1,544)	(3,121)
Total, Fair Value	92,213	169,923
Total, Unrealized Losses	(1,689)	(12,106)
Corporate debt securities
Total temporary impaired securities
Less than 12 months, Fair Value	23,938	75,368
Less than 12 months, Unrealized Losses	(125)	(1,120)
Total, Fair Value	23,938	75,368
Total, Unrealized Losses	(125)	(1,120)
U.S. Government-sponsored entities mortgage-backed securities
Total temporary impaired securities
Less than 12 months, Fair Value	119,210	909,585
Less than 12 months, Unrealized Losses	(521)	(28,386)
12 months or longer, Fair Value	403,926	4,848
12 months or longer, Unrealized Losses	(6,398)	(559)
Total, Fair Value	523,136	914,433
Total, Unrealized Losses	(6,919)	(28,945)
Non-agency collateralized mortgage-backed securities
Total temporary impaired securities
Less than 12 months, Fair Value	20,857	129,991
Less than 12 months, Unrealized Losses	(100)	(5,937)
12 months or longer, Fair Value	47,539
12 months or longer, Unrealized Losses	(927)
Total, Fair Value	68,396	129,991
Total, Unrealized Losses	$ (1,027)	$ (5,937)

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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