Loans Receivable and Allowance for Loan Losses (Summary of Loans, Allowances and Impairment Balances, by Class and Impairment Method) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Allowance for loan losses:
Individually evaluated for impairment	$ 5,643	$ 5,585
Collectively evaluated for impairment	19,355	17,525
Total allowance for loan losses	24,998	23,110
Loans receivable:
Loans evaluated individually	46,322	52,599
Loans evaluated collectively	1,952,212	1,698,273
Total loans receivable	1,998,534	1,750,872
Period used to analyze future loan losses	2 years
Commercial and industrial [Member]
Allowance for loan losses:
Individually evaluated for impairment	4,401	1,559
Collectively evaluated for impairment	7,313	6,619
Total allowance for loan losses	11,714	8,178
Loans receivable:
Loans evaluated individually	16,982	13,055
Loans evaluated collectively	508,145	434,089
Total loans receivable	525,127	447,144
Commercial tax-exempt [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	55	72
Total allowance for loan losses	55	72
Loans receivable:
Loans evaluated individually	0	0
Loans evaluated collectively	71,151	81,734
Total loans receivable	71,151	81,734
Owner occupied real estate [Member]
Allowance for loan losses:
Individually evaluated for impairment	1,242	1,366
Collectively evaluated for impairment	689	814
Total allowance for loan losses	1,931	2,180
Loans receivable:
Loans evaluated individually	7,464	5,822
Loans evaluated collectively	324,606	296,595
Total loans receivable	332,070	302,417
Commercial construction and land development [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	1,660
Collectively evaluated for impairment	4,242	3,899
Total allowance for loan losses	4,242	5,559
Loans receivable:
Loans evaluated individually	3,810	11,669
Loans evaluated collectively	134,254	121,507
Total loans receivable	138,064	133,176
Commercial real estate [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	4,707	4,161
Total allowance for loan losses	4,707	4,161
Loans receivable:
Loans evaluated individually	9,976	10,953
Loans evaluated collectively	584,300	462,235
Total loans receivable	594,276	473,188
Residential [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	524
Collectively evaluated for impairment	796	436
Total allowance for loan losses	796	960
Loans receivable:
Loans evaluated individually	5,657	7,979
Loans evaluated collectively	105,294	89,787
Total loans receivable	110,951	97,766
Consumer [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	476
Collectively evaluated for impairment	931	827
Total allowance for loan losses	931	1,303
Loans receivable:
Loans evaluated individually	2,433	3,121
Loans evaluated collectively	224,462	212,326
Total loans receivable	226,895	215,447
Unallocated Financing Receivables [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	622	697
Total allowance for loan losses	622	697
Loans receivable:
Loans evaluated individually	0	0
Loans evaluated collectively	0	0
Total loans receivable	$ 0	$ 0

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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