2. Investment Securities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Investment securities available for sale
Amortized Cost	$ 260,708	$ 272,167
Estimated Fair Value	268,821	281,099
Mortgage-backed securities
Investment securities available for sale
Amortized Cost	75,386	88,496
Gross Unrealized Gains	2,098	1,766
Gross Unrealized Losses	18	52
Estimated Fair Value	77,466	90,210
U.S. Government sponsored enterprises
Investment securities available for sale
Amortized Cost	38,793	33,766
Gross Unrealized Gains	505	418
Gross Unrealized Losses	129	136
Estimated Fair Value	39,169	34,048
State and political subdivisions
Investment securities available for sale
Amortized Cost	143,094	145,938
Gross Unrealized Gains	5,566	6,534
Gross Unrealized Losses	338	226
Estimated Fair Value	148,322	152,246
Corporate bonds
Investment securities available for sale
Amortized Cost	1,937	2,469
Gross Unrealized Gains	4	16
Gross Unrealized Losses	1	18
Estimated Fair Value	1,940	2,467
Trust preferred securities
Investment securities available for sale
Amortized Cost	750	750
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	750	750
Equity securities
Investment securities available for sale
Amortized Cost	748	748
Gross Unrealized Gains	426	630
Gross Unrealized Losses	0	0
Estimated Fair Value	1,174	1,378
Total
Investment securities available for sale
Amortized Cost	260,708	272,167
Gross Unrealized Gains	8,599	9,364
Gross Unrealized Losses	486	432
Estimated Fair Value	$ 268,821	$ 281,099

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

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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