Loans and Allowance for Loan Losses - Loans on Nonaccrual Status (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Nonaccrual Loans	$ 24,976	$ 27,796
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Nonaccrual Loans	13,630	16,349
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Nonaccrual Loans	355	472
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Nonaccrual Loans	5,335	5,622
Home equity loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Nonaccrual Loans	4,798	4,293
Indirect
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Nonaccrual Loans	486	711
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Nonaccrual Loans	$ 372	$ 349