2. Investment Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Investment securities available for sale
Amortized Cost	$ 272,230	$ 272,167
Estimated Fair Value	282,575us-gaap_AvailableForSaleSecurities	281,099us-gaap_AvailableForSaleSecurities
Mortgage-backed securities
Investment securities available for sale
Amortized Cost	86,230	88,496
Gross Unrealized Gains	2,331	1,766
Gross Unrealized Losses	8	52
Estimated Fair Value	88,553	90,210
U.S. Government sponsored enterprises
Investment securities available for sale
Amortized Cost	36,977	33,766
Gross Unrealized Gains	526	418
Gross Unrealized Losses	141	136
Estimated Fair Value	37,362	34,048
State and political subdivisions
Investment securities available for sale
Amortized Cost	145,568	145,938
Gross Unrealized Gains	7,044	6,534
Gross Unrealized Losses	138	226
Estimated Fair Value	152,474	152,246
Corporate bonds
Investment securities available for sale
Amortized Cost	1,957	2,469
Gross Unrealized Gains	11	16
Gross Unrealized Losses	5	18
Estimated Fair Value	1,963	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	725	630
Gross Unrealized Losses	0	0
Estimated Fair Value	1,473	1,378
Total
Investment securities available for sale
Amortized Cost	272,230	272,167
Gross Unrealized Gains	10,637	9,364
Gross Unrealized Losses	292	432
Estimated Fair Value	$ 282,575	$ 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

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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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