Noncovered Loans (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2013 contract	Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Loans to related parties	$ 13,700,000	$ 14,200,000
Advances on related party loans	475,000
Repayments on related party loans	948,000
Additional funds committed to lend on loans classified as TDR	1,800,000	236,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0
Loans Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	463,700,000	443,400,000
Federal Reserve Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	$ 17,400,000	$ 13,800,000