Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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STOCKHOLDERS' EQUITY AND EARNINGS PER COMMON SHARE (Details 5) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amounts reclassified out of each component of accumulated other comprehensive income
Non-interest income	$ 14,200us-gaap_NoninterestIncome	$ 14,641us-gaap_NoninterestIncome	$ 14,506us-gaap_NoninterestIncome	$ 4,423us-gaap_NoninterestIncome	$ 15,714us-gaap_NoninterestIncome	$ 12,114us-gaap_NoninterestIncome	$ 15,606us-gaap_NoninterestIncome	$ 14,798us-gaap_NoninterestIncome	$ 47,770us-gaap_NoninterestIncome	$ 58,232us-gaap_NoninterestIncome	$ 54,056us-gaap_NoninterestIncome
Tax expense	(3,875)us-gaap_IncomeTaxExpenseBenefit	(4,230)us-gaap_IncomeTaxExpenseBenefit	(4,119)us-gaap_IncomeTaxExpenseBenefit	461us-gaap_IncomeTaxExpenseBenefit	(4,762)us-gaap_IncomeTaxExpenseBenefit	(3,917)us-gaap_IncomeTaxExpenseBenefit	(4,038)us-gaap_IncomeTaxExpenseBenefit	(4,387)us-gaap_IncomeTaxExpenseBenefit	(11,763)us-gaap_IncomeTaxExpenseBenefit	(17,104)us-gaap_IncomeTaxExpenseBenefit	(13,223)us-gaap_IncomeTaxExpenseBenefit
Net income	11,398	11,988	11,464	(1,106)	10,537	8,104	12,037	10,465	33,744	41,143	33,188
Amount Reclassified From Accumulated Other Comprehensive Income (loss)
Amounts reclassified out of each component of accumulated other comprehensive income
Net income									4,831	(225)	1,895
Net unrealized holding gain on AFS securities: \| Amount Reclassified From Accumulated Other Comprehensive Income (loss)
Amounts reclassified out of each component of accumulated other comprehensive income
Non-interest income									(482)	(4,758)	(1,442)
Tax expense									196	1,920	579
Net income									(286)	(2,838)	(863)
Net loss on cash flow hedging derivatives \| Amount Reclassified From Accumulated Other Comprehensive Income (loss)
Amounts reclassified out of each component of accumulated other comprehensive income
Interest income									5,393	3,620	3,581
Tax expense									(2,201)	(1,460)	(1,441)
Net income									3,192	2,160	2,140
Net loss on terminated swap \| Amount Reclassified From Accumulated Other Comprehensive Income (loss)
Amounts reclassified out of each component of accumulated other comprehensive income
Interest income									3,237	942	942
Tax expense									(1,312)	(489)	(324)
Net income									$ 1,925	$ 453	$ 618