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
Financing Receivable, Recorded Investment [Line Items]
Troubled Debt Restructuring, Classification removed	$ 728,000		$ 3,600,000
Partial Charge-Offs On Impaired Loans			83,300,000		105,100,000
Impaired Financing Receivable, Related Allowance	9,297,000		9,297,000		8,276,000
Recorded investment, related to loans	18,000,000		18,000,000		28,800,000
TDRs included in nonaccrual loan totals	78,500,000		78,500,000		84,700,000
TDRs included in accruing loan totals	24,500,000		24,500,000		29,900,000
Nonaccrual TDRs considered current	57,200,000		57,200,000		52,600,000
Commitments to lend additional funds to borrowers whose terms had been modified in a TDR	6,900,000		6,900,000		5,000,000
Specific reserves related to troubled debt restructuring	7,700,000		7,700,000		5,600,000
Additional specific reserves related to troubled debt restructurings	474,000	167,000	745,000	1,200,000
Modified substandard commercial loans, total recorded investment	541,000	2,100,000	541,000	2,100,000
Modified substandard consumer loans, total recorded investment	19,600,000	20,500,000	19,600,000	20,500,000
Loan Modifications on Nonacrrual status	751,000	1,200,000	3,200,000	7,200,000
Loan past due period before entering default status			30 days
Financing Receivable, Modifications, Subsequent Default, Recorded Investment, During Period	5,603,000	15,705,000	7,162,000	17,240,000
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Recorded Investment [Line Items]
Partial Charge-Offs On Impaired Loans			78,500,000		96,900,000
Financing Receivable With A Related Allowance Recorded [Member]
Financing Receivable, Recorded Investment [Line Items]
Partial Charge-Offs On Impaired Loans			4,800,000		8,200,000
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Modifications, Subsequent Default, Recorded Investment, During Period	634,000	1,224,000	670,000	1,936,000
Commercial Real Estate [Member] | Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Related Allowance	0		0		0
Commercial Real Estate [Member] | Financing Receivable With A Related Allowance Recorded [Member]
Financing Receivable, Recorded Investment [Line Items]
Impaired Financing Receivable, Related Allowance	5,906,000		5,906,000		1,540,000
Accruing [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans modified during period	376,000	91,000	496,000	362,000
Nonaccrual [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans modified during period	$ 5,200,000	$ 15,600,000	$ 6,700,000	$ 16,900,000