Allowance for Loan Losses - Allowance For Loan Losses (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	$ 16,723	$ 16,282
Charge-Offs	(188)	(329)
Recoveries	86	79
Provision (benefit)	326	0
Balance, end of period	16,947	16,032
Balance, end of period: Individually evaluated for impairment	416	282
Balance, end of period: Collectively evaluated for impairment	16,531	15,750
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	5,643	5,779
Charge-Offs	(107)	(320)
Recoveries	67	54
Provision (benefit)	488	144
Balance, end of period	6,091	5,657
Balance, end of period: Individually evaluated for impairment	361	277
Balance, end of period: Collectively evaluated for impairment	5,730	5,380
Real Estate Construction One-To- Four Family
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	644	557
Charge-Offs	0	0
Recoveries	0	12
Provision (benefit)	113	(56)
Balance, end of period	757	513
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	757	513
Real Estate Construction Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	1,653	539
Charge-Offs	0	0
Recoveries	0	0
Provision (benefit)	10	84
Balance, end of period	1,663	623
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	1,663	623
Real Estate Term Owner Occupied
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	1,580	1,583
Charge-Offs	0	0
Recoveries	0	0
Provision (benefit)	(10)	(176)
Balance, end of period	1,570	1,407
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	1,570	1,407
Real Estate Term Non-Owner Occupied
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	4,704	4,297
Charge-Offs	0	0
Recoveries	0	0
Provision (benefit)	90	(4)
Balance, end of period	4,794	4,293
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	4,794	4,293
Real Estate Term Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	656	537
Charge-Offs	(81)	0
Recoveries	17	0
Provision (benefit)	164	118
Balance, end of period	756	655
Balance, end of period: Individually evaluated for impairment	55	0
Balance, end of period: Collectively evaluated for impairment	701	655
Consumer Secured By 1st Deed Of Trust
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	285	322
Charge-Offs	0	0
Recoveries	0	0
Provision (benefit)	(11)	(9)
Balance, end of period	274	313
Balance, end of period: Individually evaluated for impairment	0	5
Balance, end of period: Collectively evaluated for impairment	274	308
Consumer Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	410	390
Charge-Offs	0	(9)
Recoveries	2	13
Provision (benefit)	(10)	(10)
Balance, end of period	402	384
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	402	384
Unallocated
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance, beginning of period	1,148	2,278
Charge-Offs	0	0
Recoveries	0	0
Provision (benefit)	(508)	(91)
Balance, end of period	640	2,187
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	$ 640	$ 2,187

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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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

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

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

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

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-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

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