Loans and Allowance for Credit Losses (Details 7) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Current	$ 803,444	$ 777,792
Total past due	4,104	5,229
Nonaccrual	13,531	12,093
Total loans	$ 821,079	$ 795,114
Percent of total loans, Current	97.90%	97.80%
Percent of total loans, Total past due	0.50%	0.70%
Percent of total loans, Nonaccrual	1.60%	1.50%
Percent of total loans, Total loans	100.00%	100.00%
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	$ 1,688	$ 2,222
Percent of total loans, Total past due	0.20%	0.30%
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	$ 2,410	$ 3,000
Percent of total loans, Total past due	0.30%	0.40%
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	$ 6	$ 7
Percent of total loans, Total past due	0.00%	0.00%
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Current	$ 75,619	$ 78,082
Total past due	100	21
Nonaccrual	5,429	7,529
Total loans	81,148	85,632
Construction [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	0	21
Construction [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	100	0
Construction [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	0	0
Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Current	311,432	300,563
Total past due	2,984	4,241
Nonaccrual	5,625	2,259
Total loans	320,041	307,063
Residential real estate [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	934	2,139
Residential real estate [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	2,050	2,102
Residential real estate [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	0	0
Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Current	342,536	327,370
Total past due	991	861
Nonaccrual	2,186	2,022
Total loans	345,713	330,253
Commercial real estate [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	731	0
Commercial real estate [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	260	861
Commercial real estate [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	0	0
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Current	66,763	64,670
Total past due	4	80
Nonaccrual	192	161
Total loans	66,959	64,911
Commercial [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	4	49
Commercial [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	0	31
Commercial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	0	0
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Current	7,094	7,107
Total past due	25	26
Nonaccrual	99	122
Total loans	7,218	7,255
Consumer [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	19	13
Consumer [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	0	6
Consumer [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Total past due	$ 6	$ 7