Investment Securities - Amortized cost and approximate fair values of securities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 110,822	$ 101,863
Gross Unrealized Gains	3,535	3,645
Gross Unrealized Losses	(587)	(819)
Fair Value	113,770	104,689
Federal agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	42,581	37,107
Gross Unrealized Gains	849	844
Gross Unrealized Losses	(21)	(34)
Fair Value	43,409	37,917
State and municipal
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	29,331	27,076
Gross Unrealized Gains	1,865	1,663
Gross Unrealized Losses	(34)	(24)
Fair Value	31,162	28,715
Government-sponsored enterprise (GSE) residential mortgage-backed and other asset-backed agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	35,258	33,565
Gross Unrealized Gains	774	1,138
Gross Unrealized Losses	(10)	(6)
Fair Value	36,022	34,697
Corporate
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,652	4,115
Gross Unrealized Gains	47
Gross Unrealized Losses	(522)	(755)
Fair Value	$ 3,177	$ 3,360

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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+ Details

- Definition

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.

+ References+ Details

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References+ Details