Allowance for Loan Losses Schedule of Troubled Debt Restructurings by Loan Category and Concession Type (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Modifications, Consession Type [Line Items]
Rate reduction	$ 1,592	$ 726
Payment extension	156	2,291
Interest only	134
Rate reduction and payment extension	3,424	427
Rate reduction and interest only	108
Payment extension and interest only		1,861
Rate reduction, payment extension, and forgiveness of debt	250
Rate reduction, payment extension, interest only, and forbearance		47
A/B note structure	1,200
Additional collateral collected		204
Escrow only		256
Other	63
Total troubled debt restructurings	6,927	5,812
Commercial and industrial
Financing Receivable, Modifications, Consession Type [Line Items]
Rate reduction		0
Payment extension		956
Rate reduction and payment extension		0
Payment extension and interest only		0
Rate reduction, payment extension, interest only, and forbearance		0
Additional collateral collected		204
Escrow only		0
Total troubled debt restructurings		1,160
Commercial real estate - owner occupied
Financing Receivable, Modifications, Consession Type [Line Items]
Rate reduction	1,146	0
Payment extension	0	924
Interest only	0
Rate reduction and payment extension	2,884	0
Rate reduction and interest only	0
Payment extension and interest only		1,861
Rate reduction, payment extension, and forgiveness of debt	0
Rate reduction, payment extension, interest only, and forbearance		47
A/B note structure	1,200
Additional collateral collected		0
Escrow only		0
Other	0
Total troubled debt restructurings	5,230	2,832
Commercial real estate - non-owner occupied
Financing Receivable, Modifications, Consession Type [Line Items]
Rate reduction	0	0
Payment extension	0	114
Interest only	0
Rate reduction and payment extension	84	0
Rate reduction and interest only	0
Payment extension and interest only		0
Rate reduction, payment extension, and forgiveness of debt	0
Rate reduction, payment extension, interest only, and forbearance		0
A/B note structure	0
Additional collateral collected		0
Escrow only		0
Other	0
Total troubled debt restructurings	84	114
Commercial construction and land development
Financing Receivable, Modifications, Consession Type [Line Items]
Rate reduction	0
Payment extension	0
Interest only	0
Rate reduction and payment extension	0
Rate reduction and interest only	0
Rate reduction, payment extension, and forgiveness of debt	250
A/B note structure	0
Other	0
Total troubled debt restructurings	250
One-to-four family residential
Financing Receivable, Modifications, Consession Type [Line Items]
Rate reduction	446	726
Payment extension	156	297
Interest only	134
Rate reduction and payment extension	456	427
Rate reduction and interest only	108
Payment extension and interest only		0
Rate reduction, payment extension, and forgiveness of debt	0
Rate reduction, payment extension, interest only, and forbearance		0
A/B note structure	0
Additional collateral collected		0
Escrow only		256
Other	63
Total troubled debt restructurings	$ 1,363	$ 1,706