Securities (Details) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Available-for-sale securities:
Amortized cost	$ 209,486,000	$ 175,213,000
Gross unrealized holding gains	8,925,000	11,223,000
Gross unrealized holding losses	1,562,000	1,075,000
Fair value	216,849,000	185,361,000
Held-to-maturity securities:
Fair Value	2,501,000	2,483,000
Additional disclosures
Carrying amount of securities pledged as collateral to secure public deposits	217,100,000	185,000,000
Obligations of U.S. government agencies
Available-for-sale securities:
Amortized cost	1,816,000	1,821,000
Gross unrealized holding gains	54,000	70,000
Fair value	1,870,000	1,891,000
Obligations of state and political subdivisions
Available-for-sale securities:
Amortized cost	95,834,000	95,312,000
Gross unrealized holding gains	7,901,000	8,922,000
Gross unrealized holding losses	1,026,000	733,000
Fair value	102,709,000	103,501,000
Held-to-maturity securities:
Amortized Cost	2,225,000	2,198,000
Gross Unrealized Holding Gains	276,000	285,000
Fair Value	2,501,000	2,483,000
Government sponsored agency/ collateralized mortgage obligations
Available-for-sale securities:
Amortized cost	16,214,000	8,805,000
Gross unrealized holding gains	306,000	311,000
Gross unrealized holding losses	112,000	13,000
Fair value	16,408,000	9,103,000
Government sponsored agency/ residential mortgage-backed securities
Available-for-sale securities:
Amortized cost	94,112,000	67,765,000
Gross unrealized holding gains	664,000	1,920,000
Gross unrealized holding losses	323,000	229,000
Fair value	94,453,000	69,456,000
Corporate debt securities
Available-for-sale securities:
Amortized cost	500,000	500,000
Gross unrealized holding losses	85,000	90,000
Fair value	415,000	410,000
Equity securities
Available-for-sale securities:
Amortized cost	1,010,000	1,010,000
Gross unrealized holding losses	16,000	10,000
Fair value	$ 994,000	$ 1,000,000