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Loans (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amount of loans held for sale	$ 3,900,000		$ 3,900,000		$ 5,400,000
Purchased credit-impaired (PCI) loans held-for-investment	62,802,000		62,802,000		75,349,000
Criteria days for delinquent status			90 days
Impairment of loans	13,200,000		13,200,000		26,000,000
Principal balance of loans on non accrual status	500,000,000		500,000,000
Loans held for sale	1,700,000		1,700,000		5,400,000
Financing Receivable, Recorded Investment 90 Days or More Past Due and Accruing	18,000		18,000		621,000
Loans with carrying balances not written down	10,900,000		10,900,000		24,900,000
Average original impaired loans			47,000,000		55,000,000
Interest income on impaired loans	424,000	938,000	1,500,000	2,200,000
Troubled debt restructurings	37,200,000		37,200,000		45,000,000
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	0		0
Investment in non accrual loans	19,500,000		19,500,000		34,900,000
Loans on non accrual status with principal balances below threshold definition of an impaired loan	$ 4,700,000		$ 4,700,000		$ 4,100,000
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Purchase Credit Impaired Loans			38.00%
Loan to value ratio	35.00%		35.00%
One-to-Four Family Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratio	60.00%		60.00%
Commercial and Industrial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Purchase Credit Impaired Loans			47.00%
Multi Family [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan to value ratio	35.00%		35.00%

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