CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) [Abstract]
Net income	$ 11,208	$ 11,529	$ 61,245	$ 23,307
Amortization and reversal of net unrealized loss on securities transferred from available-for-sale to held-to-maturity, net of deferred tax expense of $6 and $10 during the three months ended June 30, 2016 and 2015, respectively, and $11 and $21 during the six months ended June 30, 2016 and 2015, respectively	8	12	14	25
Reduction in (adjustment to) non-credit component of other than temporary impairment ("OTTI"), net of deferred tax expense (benefit) of $4 and $(16) during the three months ended June 30, 2016 and 2015, respectively, and $8 and $(12) during the six months ended June 30, 2016 and 2015, respectively	4	(19)	8	(15)
Reclassification adjustment for securities sold during the period, net of income tax expense (benefit) of $2 during the three months ended June 30, 2015 and $(624) during the six months ended June 30, 2015 (reclassified from net gain on securities)	0	2	0	(760)
Net unrealized securities gains (losses) arising during the period, net of deferred tax expense (benefit) of $21 and $(2) during the three months ended June 30, 2016 and 2015, respectively, and $28 and $15 during the six months ended June 30, 2016 and 2015, respectively	26	(4)	34	20
Net unrealized derivative liability loss arising during the period, net of deferred tax benefit of $431 during both the three and six month periods ending June 30, 2016	(526)	0	(526)	0
Change in pension and other postretirement obligations, net of deferred tax expense (benefit) of $191 and $210 during the three months ended June 30, 2016 and 2015, respectively, and $382 and $(58) during the six months ended June 30, 2016 and 2015, respectively	234	257	468	(72)
Comprehensive Income	$ 10,954	$ 11,777	$ 61,243	$ 22,505