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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 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 year four 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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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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GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $)	3 Months Ended		9 Months Ended
GOODWILL AND OTHER INTANGIBLE ASSETS (Details) (USD $)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Goodwill	$ 337,438,000	$ 337,438,000	$ 337,438,000	$ 337,438,000	$ 337,438,000
Market capitalization	2,440,000,000		2,440,000,000
Total stockholders' equity	2,260,000,000		2,260,000,000
Premiums on acquired deposits	117,600,000		117,600,000		117,600,000
Accumulated amortization for premiums on acquired deposits	47,500,000		47,500,000		38,100,000
Amortization expense of premiums on acquired deposits	3,067,000	3,352,000	9,403,000	10,046,000
Estimated Future Amortization Expense of Premiums on Acquired Deposits [Abstract]
Three Months Ending December 31, 2011			2,924,000
Year Ending December 31, 2012			10,906,000
Year Ending December 31, 2013			9,365,000
Year Ending December 31, 2014			8,454,000
Year Ending December 31, 2015			7,543,000
Thereafter			30,923,000
Total			$ 70,115,000