Allowance for Loan Losses - Recorded Investment Segregated By Amounts Individually Or Collectively In Allowance For Loan Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	$ 971,909	$ 959,109
Balance, end of period: Individually evaluated for impairment	38,121	31,967
Balance, end of period: Collectively evaluated for impairment	933,788	927,142
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	327,733	313,514
Balance, end of period: Individually evaluated for impairment	31,961	26,812
Balance, end of period: Collectively evaluated for impairment	295,772	286,702
Real estate construction one-to-four family
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	31,064	31,201
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	31,064	31,201
Real estate construction other
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	58,369	80,093
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	58,369	80,093
Real estate term owner occupied
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	127,384	132,042
Balance, end of period: Individually evaluated for impairment	4,566	2,862
Balance, end of period: Collectively evaluated for impairment	122,818	129,180
Real estate term non-owner occupied
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	330,217	319,313
Balance, end of period: Individually evaluated for impairment	844	874
Balance, end of period: Collectively evaluated for impairment	329,373	318,439
Real estate term other
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	55,431	40,411
Balance, end of period: Individually evaluated for impairment	514	559
Balance, end of period: Collectively evaluated for impairment	54,917	39,852
Consumer secured by 1st deeds of trust
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	20,820	22,616
Balance, end of period: Individually evaluated for impairment	236	860
Balance, end of period: Collectively evaluated for impairment	20,584	21,756
Consumer other
Financing Receivable, Allowance for Credit Losses [Line Items]
Total financing receivables	20,891	19,919
Balance, end of period: Individually evaluated for impairment	0	0
Balance, end of period: Collectively evaluated for impairment	$ 20,891	$ 19,919

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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

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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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