GOODWILL AND OTHER INTANGIBLE ASSETS (Identifiable Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 79,090		$ 79,090
Accumulated Amortization	58,312		58,312		$ 55,270
Gross Carrying Amount					79,090
Total	949	$ 1,126	3,042	$ 3,332
Core Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	27,801		27,801
Accumulated Amortization	23,148		23,148		22,782
Gross Carrying Amount					27,801
Total	120	130	366	397
Customer Relationship Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	49,639		49,639
Accumulated Amortization	34,197		34,197		31,821
Gross Carrying Amount					49,639
Total	754	883	2,376	2,622
Non-Solicitation Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,650		1,650
Accumulated Amortization	967		967		667
Gross Carrying Amount					1,650
Total	75	$ 113	300	$ 313
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 688		$ 688
Gross Carrying Amount					$ 688