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	Mar. 31, 2015	Dec. 31, 2014
Allowance for loan losses:
Individually evaluated for impairment	$ 5,720	$ 5,643
Collectively evaluated for impairment	20,035	19,355
Total allowance for loan losses	25,755	24,998
Loans receivable:
Loans evaluated individually	46,013	46,322
Loans evaluated collectively	1,957,697	1,952,212
Total loans receivable	2,003,710	1,998,534
Commercial and industrial [Member]
Allowance for loan losses:
Individually evaluated for impairment	4,365	4,401
Collectively evaluated for impairment	7,654	7,313
Total allowance for loan losses	12,019	11,714
Loans receivable:
Loans evaluated individually	17,722	16,982
Loans evaluated collectively	518,627	508,145
Total loans receivable	536,349	525,127
Commercial tax-exempt [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	52	55
Total allowance for loan losses	52	55
Loans receivable:
Loans evaluated individually	0	0
Loans evaluated collectively	67,176	71,151
Total loans receivable	67,176	71,151
Owner occupied real estate [Member]
Allowance for loan losses:
Individually evaluated for impairment	1,355	1,242
Collectively evaluated for impairment	589	689
Total allowance for loan losses	1,944	1,931
Loans receivable:
Loans evaluated individually	6,249	7,464
Loans evaluated collectively	305,010	324,606
Total loans receivable	311,259	332,070
Commercial construction and land development [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	4,529	4,242
Total allowance for loan losses	4,529	4,242
Loans receivable:
Loans evaluated individually	3,670	3,810
Loans evaluated collectively	133,393	134,254
Total loans receivable	137,063	138,064
Commercial real estate [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	4,945	4,707
Total allowance for loan losses	4,945	4,707
Loans receivable:
Loans evaluated individually	10,504	9,976
Loans evaluated collectively	596,896	584,300
Total loans receivable	607,400	594,276
Residential [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	803	796
Total allowance for loan losses	803	796
Loans receivable:
Loans evaluated individually	5,639	5,657
Loans evaluated collectively	110,504	105,294
Total loans receivable	116,143	110,951
Consumer [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	870	931
Total allowance for loan losses	870	931
Loans receivable:
Loans evaluated individually	2,229	2,433
Loans evaluated collectively	226,091	224,462
Total loans receivable	228,320	226,895
Unallocated [Member]
Allowance for loan losses:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	593	622
Total allowance for loan losses	593	622
Loans receivable:
Loans evaluated individually	0	0
Loans evaluated collectively	0	0
Total loans receivable	$ 0	$ 0

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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

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-Publisher FASB

-Name Accounting Standards Codification

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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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