Investment Securities - Portfolio of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized Cost	$ 325,888	$ 344,416
Gross Unrealized Gains	2,718	2,479
Gross Unrealized Losses	2,384	5,022
Fair Value	326,222	341,873
Obligations of state and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized Cost	23,929	29,935
Gross Unrealized Gains	233	226
Gross Unrealized Losses	352	1,020
Fair Value	23,810	29,141
GSE mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized Cost	61,578	72,144
Gross Unrealized Gains	1,304	1,736
Gross Unrealized Losses	22	302
Fair Value	62,860	73,578
Collateralized mortgage obligations: residential
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized Cost	211,808	223,602
Gross Unrealized Gains	359	206
Gross Unrealized Losses	1,958	3,606
Fair Value	210,209	220,202
Collateralized mortgage obligations: commercial
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized Cost	2,499	3,135
Gross Unrealized Gains	0	0
Gross Unrealized Losses	27	53
Fair Value	2,472	3,082
Mutual funds
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized Cost	2,100	2,100
Gross Unrealized Gains	0	0
Gross Unrealized Losses	21	41
Fair Value	2,079	2,059
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale, Amortized Cost	23,974	13,500
Gross Unrealized Gains	822	311
Gross Unrealized Losses	4	0
Fair Value	$ 24,792	$ 13,811

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
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-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
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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
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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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