Investment Securities Security Type - Available for Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	$ 321,197	$ 262,837
Investment securities available for sale, gross unrealized gains	2,780	1,066
Investment securities available for sale, gross unrealized (losses)	(1,380)	(3,266)
Investment securities available for sale, at fair value	322,597	260,637
US government agencies and corporations [Member]
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	2,500	2,524
Investment securities available for sale, gross unrealized gains	0	69
Investment securities available for sale, gross unrealized (losses)	0	0
Investment securities available for sale, at fair value	2,500	2,593
State and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	89,699	64,551
Investment securities available for sale, gross unrealized gains	1,687	376
Investment securities available for sale, gross unrealized (losses)	(73)	(591)
Investment securities available for sale, at fair value	91,313	64,336
Collateralized mortgage obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	110,725	103,038
Investment securities available for sale, gross unrealized gains	235	255
Investment securities available for sale, gross unrealized (losses)	(664)	(1,343)
Investment securities available for sale, at fair value	110,296	101,950
Mortgage-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	71,070	80,614
Investment securities available for sale, gross unrealized gains	453	341
Investment securities available for sale, gross unrealized (losses)	(129)	(797)
Investment securities available for sale, at fair value	71,394	80,158
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	16,786
Investment securities available for sale, gross unrealized gains	99
Investment securities available for sale, gross unrealized (losses)	0
Investment securities available for sale, at fair value	16,885
Trust preferred security [Member]
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	2,125	1,784
Investment securities available for sale, gross unrealized gains	0	0
Investment securities available for sale, gross unrealized (losses)	(450)	(534)
Investment securities available for sale, at fair value	1,675	1,250
Corporate notes
Schedule of Available-for-sale Securities [Line Items]
Investment securities available for sale, amortized cost	28,292	10,326
Investment securities available for sale, gross unrealized gains	306	25
Investment securities available for sale, gross unrealized (losses)	(64)	(1)
Investment securities available for sale, at fair value	$ 28,534	$ 10,350

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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