Investment Securities - Amortized Cost and Fair Values of Investment Securities Available for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Available for sale (AFS)
Amortized Cost	$ 151,703	$ 175,766
Gross Unrealized Gains	3,686	3,436
Gross Unrealized Losses	(1,680)	(3,045)
Available for sale	153,709	176,157
Debt securities
Available for sale (AFS)
Amortized Cost	140,378	160,155
Gross Unrealized Gains	2,837	2,266
Gross Unrealized Losses	(1,405)	(2,596)
Available for sale	141,810	159,825
U.S. Government and agency securities
Available for sale (AFS)
Amortized Cost	3,474	3,586
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(2)	(37)
Available for sale	3,476	3,549
Mortgage-backed securities
Available for sale (AFS)
Amortized Cost	9,465	9,785
Gross Unrealized Gains	337	284
Gross Unrealized Losses	(51)	(60)
Available for sale	9,751	10,009
Asset-backed securities
Available for sale (AFS)
Amortized Cost	1,826	1,960
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(33)	(20)
Available for sale	1,793	1,940
State and political securities
Available for sale (AFS)
Amortized Cost	68,533	84,992
Gross Unrealized Gains	2,044	1,797
Gross Unrealized Losses	(2)	(234)
Available for sale	70,575	86,555
Other debt securities
Available for sale (AFS)
Amortized Cost	57,080	59,832
Gross Unrealized Gains	452	185
Gross Unrealized Losses	(1,317)	(2,245)
Available for sale	56,215	57,772
Other equity securities
Available for sale (AFS)
Amortized Cost	11,325	15,611
Gross Unrealized Gains	849	1,170
Gross Unrealized Losses	(275)	(449)
Available for sale	11,899	16,332
Financial institution equity securities
Available for sale (AFS)
Amortized Cost	8,924	10,397
Gross Unrealized Gains	834	1,100
Gross Unrealized Losses	(23)	(14)
Available for sale	9,735	11,483
Other equity securities
Available for sale (AFS)
Amortized Cost	2,401	5,214
Gross Unrealized Gains	15	70
Gross Unrealized Losses	(252)	(435)
Available for sale	$ 2,164	$ 4,849

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)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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