Loans and Allowance for Loan Losses - Impaired Loans (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment, Total	$ 25,862		$ 25,862		$ 26,167
Unpaid Principal Balance, Total	33,720		33,720		34,156
Related Allowance, Total	1,669		1,669		1,673
Average Recorded Balance, Total	26,500	30,667	26,388	30,971
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment	17,629		17,629		15,378
Unpaid Principal Balance	24,502		24,502		20,086
Related Allowance	0		0		0
Average Recorded Balance	18,332	9,121	17,347	9,758
Recorded Investment	4,754		4,754		7,942
Unpaid Principal Balance	5,173		5,173		9,876
Related Allowance	1,566		1,566		1,449
Average Recorded Balance	4,830	19,600	5,867	19,511
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment	161		161		138
Unpaid Principal Balance	213		213		138
Related Allowance	0		0		0
Average Recorded Balance	142	208	141	177
Recorded Investment	342		342		459
Unpaid Principal Balance	342		342		459
Related Allowance	103		103		209
Average Recorded Balance	392	313	414	269
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment	1,991		1,991		1,610
Unpaid Principal Balance	2,298		2,298		1,686
Related Allowance	0		0		0
Average Recorded Balance	1,991	1,353	1,864	1,184
Recorded Investment	0		0		181
Unpaid Principal Balance	0		0		1,452
Related Allowance	0		0		15
Average Recorded Balance	0	72	60	72
Home equity loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment	686		686		398
Unpaid Principal Balance	870		870		398
Related Allowance	0		0		0
Average Recorded Balance	584	0	522	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Balance				0
Indirect
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment	225		225		0
Unpaid Principal Balance	248		248		0
Related Allowance	0		0		0
Average Recorded Balance	162	0	108	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Balance	0	0	0	0
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Recorded Investment	74		74		61
Unpaid Principal Balance	74		74		61
Related Allowance	0		0		0
Average Recorded Balance	67	0	65	0
Recorded Investment	0		0		0
Unpaid Principal Balance	0		0		0
Related Allowance	0		0		0
Average Recorded Balance	$ 0	$ 0	$ 0	$ 0