GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 48,400	$ 48,390
Accumulated Amortization	(34,368)	(30,959)
Net Carrying Amount	14,032	17,431
Finite-lived intangible assets, future amortization expense [Abstract]
Oct - Dec 2013	1,034
2014	3,599
2015	2,806
2016	2,096
2017	1,479
Thereafter	3,018
Net Carrying Amount	14,032	17,431
Components of goodwill [Abstract]
Goodwill	374,527	374,527
Goodwill, Activity	0
Accumulated Impairment	(4,824)	(4,824)
Accumulated impairment, Activity	0
Goodwill, net	369,703	369,703	369,703
Goodwill, net, Activity	0
Core Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	38,958	38,958
Accumulated Amortization	(27,186)	(24,466)
Net Carrying Amount	11,772	14,492
Finite-lived intangible assets, future amortization expense [Abstract]
Net Carrying Amount	11,772	14,492
Other Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9,442	9,432
Accumulated Amortization	(7,182)	(6,493)
Net Carrying Amount	2,260	2,939
Finite-lived intangible assets, future amortization expense [Abstract]
Net Carrying Amount	$ 2,260	$ 2,939