Earnings Per Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Net Income (Numerator)
Basic (in dollars)	$ 2,633	$ 607	$ 476	$ 493	$ 1,158	$ 1,113	$ 875	$ 486	$ 4,209	$ 3,632	$ 1,730
Diluted (in dollars)									$ 4,209	$ 3,632	$ 1,730
Shares (Denominator)
Basic (in shares)									5,455,000	5,414,000	5,353,000
Effective dilutive securities - Common stock options (in shares)									200,000	120,000	60,000
Diluted (in shares)									5,655,000	5,534,000	5,413,000
Per Share Amount
Basic income per share (in dollars per share)	$ 0.48	$ 0.11	$ 0.09	$ 0.09	$ 0.21	$ 0.21	$ 0.16	$ 0.09	$ 0.77	$ 0.67	$ 0.32
Effective dilutive securities - Common stock options (in dollars per share)									$ (0.03)	$ (0.01)
Diluted income per share (in dollars per share)	$ 0.47	$ 0.11	$ 0.08	$ 0.08	$ 0.20	$ 0.20	$ 0.16	$ 0.09	$ 0.74	$ 0.66	$ 0.32
Common stock options excluded from diluted earnings per share as effect of inclusion would be anti-dilutive (in shares)									696,000	918,000	9,000