Loans - Schedule of Loans Held for Investment and ALL on the basis of Impairment Method (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	$ 26,250	$ 43,913
Allowance for loan losses, Individually evaluated for impairment	2,574	11,543
Loans held for investment, Collectively evaluated for impairment	2,907,855	2,655,292
Allowance for loan losses, Collectively evaluated for impairment	30,719	29,143
Commercial
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	20,279	33,927
Allowance for loan losses, Individually evaluated for impairment	2,220	10,975
Loans held for investment, Collectively evaluated for impairment	1,197,453	1,141,452
Allowance for loan losses, Collectively evaluated for impairment	13,178	13,240
Real estate - mortgage
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	3,758	6,521
Allowance for loan losses, Individually evaluated for impairment	147	320
Loans held for investment, Collectively evaluated for impairment	1,167,365	1,009,747
Allowance for loan losses, Collectively evaluated for impairment	11,328	10,052
Construction and land
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	1,919	2,610
Allowance for loan losses, Individually evaluated for impairment	109	192
Loans held for investment, Collectively evaluated for impairment	172,532	198,671
Allowance for loan losses, Collectively evaluated for impairment	1,888	1,919
Consumer
Allowance for loan losses
Loans held for investment, Individually evaluated for impairment	294	855
Allowance for loan losses, Individually evaluated for impairment	98	56
Loans held for investment, Collectively evaluated for impairment	266,719	252,462
Allowance for loan losses, Collectively evaluated for impairment	2,705	2,536
Other
Allowance for loan losses
Loans held for investment, Collectively evaluated for impairment	103,786	52,960
Allowance for loan losses, Collectively evaluated for impairment	945	643
Unallocated
Allowance for loan losses
Allowance for loan losses, Collectively evaluated for impairment	$ 675	$ 753

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=49124121&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=49124121&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=49124121&loc=SL6953423-111524

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