Board of Directors granted stock options (Details) (USD $)	Jun. 03, 2012	Jan. 12, 2012	Dec. 14, 2011	Aug. 12, 2011	May 13, 2011	Apr. 06, 2011
Granted Stock option details
Board of Directors granted stock options to purchase shares of common stock	3,400	480	10,000	480	3,000	169,450
Granted Stock option exercise price per share	$ 13.60	$ 1.25	$ 3.75	$ 12.50	$ 15.00	$ 16.25
The weighted average fair value of the options granted was estimated per share	$ 3.88	$ 1.00	$ 2.00	$ 10.75		$ 14.60
These options vest over three years and have a term of	10	10	10	10		10