Loans and Allowance for Credit Losses (Details 6) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	$ 821,079	$ 795,114
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	81,148	85,632
Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	320,041	307,063
Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	345,713	330,253
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	66,959	64,911
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	7,218	7,255
Pass/Performing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	764,521	734,244
Pass/Performing [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	67,567	70,214
Pass/Performing [Member] | Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	303,447	290,857
Pass/Performing [Member] | Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	320,593	302,438
Pass/Performing [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	65,795	63,628
Pass/Performing [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	7,119	7,107
Special Mention [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	27,513	32,540
Special Mention [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	4,061	3,903
Special Mention [Member] | Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	6,739	8,837
Special Mention [Member] | Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	15,980	18,699
Special Mention [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	733	1,075
Special Mention [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	0	26
Substandard [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	29,045	28,330
Substandard [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	9,520	11,515
Substandard [Member] | Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	9,855	7,369
Substandard [Member] | Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	9,140	9,116
Substandard [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	431	208
Substandard [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	99	122
Doubtful [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	0	0
Doubtful [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	0	0
Doubtful [Member] | Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	0	0
Doubtful [Member] | Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	0	0
Doubtful [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	0	0
Doubtful [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	$ 0	$ 0