OTHER COMPREHENSIVE INCOME (Details 2) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Amounts Reclassified from AOCI
Realized gains on sale of available for sale securities		$ 383		$ 449
Total reclassifications, before income tax	$ 13,346	13,518	$ 26,833	26,788
Income tax benefit (expense)	(4,505)	(4,664)	(8,821)	(9,308)
Net income	8,841	8,854	18,012	17,480
Amount Reclassified from Accumulated Other Comprehensive Income
Amounts Reclassified from AOCI
Total reclassifications, before income tax	(572)	45	(961)	(233)
Income tax benefit (expense)	234	(18)	393	94
Net income	(338)	27	(568)	(139)
Amount Reclassified from Accumulated Other Comprehensive Income \| Net securities gains
Amounts Reclassified from AOCI
Realized gains on sale of available for sale securities		383		449
Amount Reclassified from Accumulated Other Comprehensive Income \| Amortization of defined benefit pension plan and the defined benefit plan component of the SERP
Amounts Reclassified from AOCI
Prior service credit	19	19	38	38
Transition obligation	(7)	(7)	(14)	(14)
Actuarial losses	(125)	(111)	(251)	(217)
Amount Reclassified from Accumulated Other Comprehensive Income \| Realized losses on cash flow hedges
Amounts Reclassified from AOCI
Gain (loss) on interest rate contracts reclassified to interest expense	$ (459)	$ (239)	$ (734)	$ (489)

The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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