Investment Securities - Amortized Cost and Fair Values of Investment Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Available for sale (AFS)
Amortized Cost	$ 137,336	$ 134,460
Gross Unrealized Gains	1,673	1,954
Gross Unrealized Losses	(2,099)	(2,922)
Available for sale	136,910	133,492
Debt securities
Available for sale (AFS)
Amortized Cost	126,805	123,227
Gross Unrealized Gains	1,006	985
Gross Unrealized Losses	(2,050)	(2,738)
Available for sale	125,761	121,474
Mortgage-backed securities
Available for sale (AFS)
Amortized Cost	5,057	9,295
Gross Unrealized Gains	128	182
Gross Unrealized Losses	(113)	(164)
Available for sale	5,072	9,313
Asset-backed securities
Available for sale (AFS)
Amortized Cost	56	109
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Available for sale	56	109
State and political securities
Available for sale (AFS)
Amortized Cost	64,809	60,777
Gross Unrealized Gains	758	666
Gross Unrealized Losses	(237)	(509)
Available for sale	65,330	60,934
Other debt securities
Available for sale (AFS)
Amortized Cost	56,883	53,046
Gross Unrealized Gains	120	137
Gross Unrealized Losses	(1,700)	(2,065)
Available for sale	55,303	51,118
Financial institution equity securities
Available for sale (AFS)
Amortized Cost	9,231	9,566
Gross Unrealized Gains	667	969
Gross Unrealized Losses	0	0
Available for sale	9,898	10,535
Non-financial institution equity securities
Available for sale (AFS)
Amortized Cost	1,300	1,667
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(49)	(184)
Available for sale	1,251	1,483
Other equity securities
Available for sale (AFS)
Amortized Cost	10,531	11,233
Gross Unrealized Gains	667	969
Gross Unrealized Losses	(49)	(184)
Available for sale	$ 11,149	$ 12,018

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
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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