Noncovered Loans (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012 contract loan	Dec. 31, 2011	Dec. 31, 2010
Financing Receivable, Recorded Investment [Line Items]
Loans to related parties	$ 14,200,000	$ 9,000,000
Advances on related party loans	7,700,000
Repayments on related party loans	2,500,000
Commercial and residential real estate loans pledged as FHLB collateral	443,419,000	539,454,000
Federal Reserve Bank, Advances, Collateral Pledged	59,456,000	404,444,000
Loans and Leases Receivable, Impaired, Nonperforming, Nonaccrual of Interest	37,400,000	53,500,000
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	3,400,000	5,300,000	6,400,000
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing, Number of Loans	0
Loans and Leases Receivable, Nonaccrual of Interest, Commitments of Additional Funds	346,000	2,000,000
Financing Receivable Modifications Additional Commitment To Lend	236,000	535,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0
Loans Receivable [Member]
Financing Receivable, Recorded Investment [Line Items]
Commercial and residential real estate loans pledged as FHLB collateral	$ 443,419,000	$ 462,040,000