Loans Receivable, Net (Details Textual) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Troubled Debt Restructurings
Percentage of Troubled Debt Restructurings Resulting from Extensions of Maturity Date	71.00%	49.00%	58.00%
TDR With Pre Modification Loan Balance for Which Oreo Was Received	$ 18,345,000	$ 39,769,000	$ 96,528,000
Additional outstanding commitments on TDRs	2,024,000	4,534,000
Charge-offs on TDRs	1,945,000	6,271,000	8,792,000
Loans Receivable
Percentage of consolidated stockholders equity exceeding which no borrower had outstanding loans or commitments	10.00%
Net deferred fees, premiums, and discounts included in the loan receivable	10,662,000	1,379,000
Variable rate loans	2,566,042,000
Fixed rate loans	1,496,796,000
Weighted average interest rate on loans	5.04%	5.33%
Loan sold and serviced for others	148,376,000	116,439,000	160,465,000
Loans pledged as collateral	2,579,874,000
Aggregate amount of loans outstanding to related parties	35,224,000	33,869,000
New loans to related parties	4,311,000
Repayments of loans by related parties	2,956,000
Interest income that would have been recorded on non-accrual loans	$ 4,122,000	$ 5,161,000	$ 7,441,000
Commercial Real Estate
Troubled Debt Restructurings
Percentage of Troubled Debt Restructurings Resulting from Extensions of Maturity Date	87.00%	36.00%	56.00%
Percentage of TDRs Resulting of Combination of Interest Rate Reduction Extension of Maturity Date or Reduction in Face Amount	9.00%	30.00%	31.00%

Additional outstanding commitments on TDRs.

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Loans receivable with fixed rate of interest.

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Loans receivable with variable rate of interest.

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No definition available.

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Percentage of consolidated stockholders equity exceeding which no borrower had outstanding loans or commitments.

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No definition available.

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Percentage of TDRs resulting from extensions of maturity date.

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No definition available.

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Percentage of TDRs resulting of a combination of interest rate reduction, extension of maturity date, or reduction in face amount.

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No definition available.

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TDR with pre modification loan balance, for which OREO was received.

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Weighted average interest rate on loans.

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Reflects the amount of the write-down related to a troubled debt restructuring.

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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

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Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

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Reflects the amount of collections received from related parties to reduce the carrying amounts of loans and leases receivable due from them.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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