Stockholders' Equity (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2011
Summary of the Company's stock option activity and related information
Outstanding, Number of shares, Beginning Balance	1,217,146
Granted, Number of shares
Forfeited, Number of shares	(5,064)
Exercised, Number of shares	(398,315)
Outstanding, Number of shares, Ending Balance	813,767
Weighted Average Exercise Price, Beginning Period	$ 12.90
Weighted Average Exercise Price, Granted	$ 0.00
Weighted Average Exercise Price, Forfeited	$ 10.61
Weighted Average Exercise Price, Exercised	$ 12.95
Weighted Average Exercise Price, Ending Period	$ 12.89