Loans - Schedule of Loans Held for Investment and ALL on the basis of Impairment Method (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	$ 38,068	$ 26,250
Allowance for loan losses, Individually evaluated for impairment	3,642	2,574
Loans held for investment, Collectively evaluated for impairment	3,083,630	2,907,855
Allowance for loan losses, Collectively evaluated for impairment	33,208	30,719
Commercial
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	33,585	20,279
Allowance for loan losses, Individually evaluated for impairment	3,362	2,220
Loans held for investment, Collectively evaluated for impairment	1,218,230	1,197,453
Allowance for loan losses, Collectively evaluated for impairment	12,989	13,178
Real estate - mortgage
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	2,453	3,758
Allowance for loan losses, Individually evaluated for impairment	77	147
Loans held for investment, Collectively evaluated for impairment	1,256,453	1,167,365
Allowance for loan losses, Collectively evaluated for impairment	12,563	11,328
Construction and land
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	1,792	1,919
Allowance for loan losses, Individually evaluated for impairment	122	109
Loans held for investment, Collectively evaluated for impairment	213,380	172,532
Allowance for loan losses, Collectively evaluated for impairment	3,324	1,888
Consumer
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	238	294
Allowance for loan losses, Individually evaluated for impairment	81	98
Loans held for investment, Collectively evaluated for impairment	287,062	266,719
Allowance for loan losses, Collectively evaluated for impairment	2,464	2,705
Other
Allowance for loan losses
Loans held for investment, Collectively evaluated for impairment	108,505	103,786
Allowance for loan losses, Collectively evaluated for impairment	981	945
Unallocated
Allowance for loan losses
Allowance for loan losses, Collectively evaluated for impairment	$ 887	$ 675

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

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=66008989&loc=SL6953423-111524

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+ 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 (h)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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The balance of financing receivables 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 (h)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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