GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 41,868	$ 41,866
Accumulated Amortization	(27,438)	(26,352)
Net Carrying Amount	14,430	15,514
Finite-lived intangible assets, future amortization expense [Abstract]
Apr - Dec 2012	3,027
2013	3,305
2014	2,579
2015	1,905
2016	1,314
Thereafter	2,300
Total	14,430
Components of goodwill [Abstract]
Goodwill	349,874	349,874
Goodwill Activity	0
Accumulated Impairment	(4,824)	(4,824)
Goodwill, Net	345,050	345,050	297,692
Core Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	32,437	32,437
Accumulated Amortization	(21,722)	(20,918)
Net Carrying Amount	10,715	11,519
Other Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9,431	9,429
Accumulated Amortization	(5,716)	(5,434)
Net Carrying Amount	$ 3,715	$ 3,995

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The accumulated amount of amortization of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

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Sum of the gross carrying amounts before accumulated amortization as of the balance sheet date of all intangible assets having statutory or estimated useful lives. The aggregate gross carrying amount (including any previously recognized impairment charges) of a major finite-lived intangible asset class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The aggregate sum of gross carrying value of a major finite-lived intangible asset class, less accumulated amortization and any impairment charges. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The amount of amortization expense expected to be recognized for the remainder of the finite-lived intangible asset useful life after the fifth succeeding fiscal year.

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The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation.

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Gross amount, as of the balance sheet date, of the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable), in excess of the fair value of net assets acquired in one or more business combination transactions.

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The accumulated impairment losses related to goodwill as of the balance sheet date.

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