OTHER COMPREHENSIVE INCOME (LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Other Comprehensive Income (Loss) [Abstract]
Change in unrealized loss on securities transferred to held to maturity, after tax	$ 12	$ 10	$ 25	$ 22
Tax expense (benefit)	7,987	7,531	15,912	14,708
Net income	11,529	10,460	23,307	20,494
Change in net unrealized gain during the period, tax	(2)	57	15	27
Change in net unrealized gain during the period, after tax	(4)	70	20	33
Total defined benefit plans, tax	210	117	(58)	234
Change in pension and other postretirement obligations, net of deferred tax expense (benefit) of $210 and $117 during the three months ended June 30, 2015 and 2014, respectively and $(58) and $234 during the six months ended June 30, 2015 and 2014, respectively	257	144	(72)	288
Total other comprehensive income, before tax	450	414	(1,460)	636
Total other comprehensive income, tax	202	186	(658)	285
Net other comprehensive income during during the period	248	228	(802)	351
Securities Held-To-Maturity and Transferred Securities [Member]
Other Comprehensive Income (Loss) [Abstract]
Change in non-credit component of OTTI, pre-tax	(35)	8	(27)	16
Change in non-credit component of OTTI, tax	(16)	4	(12)	8
Change in non-credit component of OTTI, after tax	(19)	4	(15)	8
Change in unrealized loss on securities transferred to held to maturity, pre-tax	22	18	46	38
Change in unrealized loss on securities transferred to held to maturity, tax	10	8	21	16
Change in unrealized loss on securities transferred to held to maturity, after tax	12	10	25	22
Total Securities held to maturity and transferred securities before tax	(13)	26	19	54
Total securities held to maturity and transferred tax	(6)	12	9	24
Total securities held to maturity and transferred securities, after tax	(7)	14	10	30
Securities Available-For-Sale [Member]
Other Comprehensive Income (Loss) [Abstract]
Change in net unrealized gain during the period, pre-tax	(8)	127	35	60
Change in net unrealized gain during the period, tax	(4)	57	15	27
Change in net unrealized gain during the period, after tax	(4)	70	20	33
Total securities available-for-sale, pre-tax	(4)	127	(1,349)	60
Total securities available-for-sale, tax	(2)	57	(609)	27
Total securities available-for-sale, after tax	(2)	70	(740)	33
Securities Available-For-Sale [Member] | Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Other Comprehensive Income (Loss) [Abstract]
Reclassification adjustment for net gains included in net gain on securities	4	0	(1,384)	0
Tax expense (benefit)	2	0	(624)	0
Net income	2	0	(760)	0
Defined Benefit Plans [Member]
Other Comprehensive Income (Loss) [Abstract]
Change in the net actuarial gain or loss, pre-tax	0		(1,064)
Change in the net actuarial gain or loss, tax	0		(478)
Change in the net actuarial gain or loss, after tax	0		(586)
Total defined benefit plans, pre-tax	467	261	(130)	522
Total defined benefit plans, tax	210	117	(58)	234
Change in pension and other postretirement obligations, net of deferred tax expense (benefit) of $210 and $117 during the three months ended June 30, 2015 and 2014, respectively and $(58) and $234 during the six months ended June 30, 2015 and 2014, respectively	257	144	(72)	288
Defined Benefit Plans [Member] | Reclassification Out Of Accumulated Other Comprehensive Income [Member]
Other Comprehensive Income (Loss) [Abstract]
Reclassification adjustment for expense included in salaries and employee benefits expense	467	261	934	522
Tax expense (benefit)	210	117	420	234
Net income	$ 257	$ 144	$ 514	$ 288