Loans and Allowance for Credit Losses (Details 5) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	$ 721,605	$ 710,746
Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	77,697	69,157
Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	264,424	273,336
Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	316,389	305,788
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	55,079	52,671
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	8,016	9,794
Pass/Performing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	653,917	640,698
Pass/Performing [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	60,330	52,241
Pass/Performing [Member] | Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	245,964	252,643
Pass/Performing [Member] | Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	286,695	275,573
Pass/Performing [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	53,076	50,583
Pass/Performing [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	7,852	9,658
Special Mention [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	33,102	34,256
Special Mention [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	3,472	5,643
Special Mention [Member] | Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	7,646	6,675
Special Mention [Member] | Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	20,047	20,040
Special Mention [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	1,896	1,885
Special Mention [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	41	13
Substandard [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	34,562	35,703
Substandard [Member] | Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	13,895	11,273
Substandard [Member] | Residential real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	10,790	14,018
Substandard [Member] | Commercial real estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	9,647	10,175
Substandard [Member] | Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	107	114
Substandard [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	123	123
Doubtful [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	24	89
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	24	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	89
Doubtful [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan Risk Rating	$ 0	$ 0