INVESTMENT SECURITIES (Details 3) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015 item	Dec. 31, 2014 item
INVESTMENT SECURITIES.
Number of investment securities in an unrealized loss position	121	195
Total temporary impaired securities
Less than 12 months, Fair Value	$ 210,165	$ 187,596
Less than 12 months, Unrealized Losses	(1,636)	(891)
12 months or longer, Fair Value	199,533	520,087
12 months or longer, Unrealized Losses	(2,605)	(8,869)
Total, Fair Value	409,698	707,683
Total, Unrealized Losses	(4,241)	(9,760)
States and political subdivisions debt securities
Total temporary impaired securities
Less than 12 months, Fair Value	34,821	23,591
Less than 12 months, Unrealized Losses	(257)	(145)
12 months or longer, Fair Value	23,447	68,622
12 months or longer, Unrealized Losses	(606)	(1,544)
Total, Fair Value	58,268	92,213
Total, Unrealized Losses	(863)	(1,689)
Corporate debt securities
Total temporary impaired securities
Less than 12 months, Fair Value		23,938
Less than 12 months, Unrealized Losses		(125)
Total, Fair Value		23,938
Total, Unrealized Losses		(125)
U.S. Government-sponsored entities mortgage-backed securities
Total temporary impaired securities
Less than 12 months, Fair Value	143,680	119,210
Less than 12 months, Unrealized Losses	(1,298)	(521)
12 months or longer, Fair Value	176,086	403,926
12 months or longer, Unrealized Losses	(1,999)	(6,398)
Total, Fair Value	319,766	523,136
Total, Unrealized Losses	(3,297)	(6,919)
Non-agency collateralized mortgage-backed securities
Total temporary impaired securities
Less than 12 months, Fair Value	31,664	20,857
Less than 12 months, Unrealized Losses	(81)	(100)
12 months or longer, Fair Value		47,539
12 months or longer, Unrealized Losses		(927)
Total, Fair Value	31,664	68,396
Total, Unrealized Losses	$ (81)	$ (1,027)

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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