Loans (Details 5) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Risk category of loans by portfolio segment
Loans - Gross	$ 485,025	$ 501,535
Agricultural Real Estate [Member]
Risk category of loans by portfolio segment
Loans - Gross	35,898	40,143
Agricultural Real Estate [Member] \| 1-2 [Member]
Risk category of loans by portfolio segment
Loans - Gross	2,255	2,719
Agricultural Real Estate [Member] \| 3 [Member]
Risk category of loans by portfolio segment
Loans - Gross	13,837	15,111
Agricultural Real Estate [Member] \| 4 [Member]
Risk category of loans by portfolio segment
Loans - Gross	18,979	21,481
Agricultural Real Estate [Member] \| 5 [Member]
Risk category of loans by portfolio segment
Loans - Gross	790	794
Agricultural Real Estate [Member] \| 6 [Member]
Risk category of loans by portfolio segment
Loans - Gross	37	38
Agricultural Real Estate [Member] \| 8 [Member]
Risk category of loans by portfolio segment
Loans - Gross
Agricultural [Member]
Risk category of loans by portfolio segment
Loans - Gross	51,896	57,770
Agricultural [Member] \| 1-2 [Member]
Risk category of loans by portfolio segment
Loans - Gross	2,883	5,022
Agricultural [Member] \| 3 [Member]
Risk category of loans by portfolio segment
Loans - Gross	16,509	23,525
Agricultural [Member] \| 4 [Member]
Risk category of loans by portfolio segment
Loans - Gross	32,469	29,188
Agricultural [Member] \| 5 [Member]
Risk category of loans by portfolio segment
Loans - Gross	35	35
Agricultural [Member] \| 8 [Member]
Risk category of loans by portfolio segment
Loans - Gross
Commercial Real Estate [Member]
Risk category of loans by portfolio segment
Loans - Gross	209,601	199,999
Commercial Real Estate [Member] \| 1-2 [Member]
Risk category of loans by portfolio segment
Loans - Gross	3,264	4,046
Commercial Real Estate [Member] \| 3 [Member]
Risk category of loans by portfolio segment
Loans - Gross	52,354	42,467
Commercial Real Estate [Member] \| 4 [Member]
Risk category of loans by portfolio segment
Loans - Gross	139,030	137,537
Commercial Real Estate [Member] \| 5 [Member]
Risk category of loans by portfolio segment
Loans - Gross	8,672	8,984
Commercial Real Estate [Member] \| 6 [Member]
Risk category of loans by portfolio segment
Loans - Gross	6,237	6,295
Commercial Real Estate [Member] \| 7 [Member]
Risk category of loans by portfolio segment
Loans - Gross	44	670
Commercial Real Estate [Member] \| 8 [Member]
Risk category of loans by portfolio segment
Loans - Gross
Commercial and Industrial [Member]
Risk category of loans by portfolio segment
Loans - Gross	89,779	101,624
Commercial and Industrial [Member] \| 1-2 [Member]
Risk category of loans by portfolio segment
Loans - Gross	57	750
Commercial and Industrial [Member] \| 3 [Member]
Risk category of loans by portfolio segment
Loans - Gross	22,021	21,750
Commercial and Industrial [Member] \| 4 [Member]
Risk category of loans by portfolio segment
Loans - Gross	60,990	71,228
Commercial and Industrial [Member] \| 5 [Member]
Risk category of loans by portfolio segment
Loans - Gross	2,404	3,385
Commercial and Industrial [Member] \| 6 [Member]
Risk category of loans by portfolio segment
Loans - Gross	1,600	2,202
Commercial and Industrial [Member] \| 7 [Member]
Risk category of loans by portfolio segment
Loans - Gross	2,707	2,309
Commercial and Industrial [Member] \| 8 [Member]
Risk category of loans by portfolio segment
Loans - Gross
Industrial Development Bonds [Member]
Risk category of loans by portfolio segment
Loans - Gross	1,202	1,299
Industrial Development Bonds [Member] \| 1-2 [Member]
Risk category of loans by portfolio segment
Loans - Gross		97
Industrial Development Bonds [Member] \| 3 [Member]
Risk category of loans by portfolio segment
Loans - Gross	858	859
Industrial Development Bonds [Member] \| 4 [Member]
Risk category of loans by portfolio segment
Loans - Gross	344	343
Industrial Development Bonds [Member] \| 8 [Member]
Risk category of loans by portfolio segment
Loans - Gross