Stock-Based Compensation (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011
Summary of the activity in the Company's stock option plan
Outstanding Beginning, Number of Options	280,000	620,000	620,000
Outstanding Ending, Number of Options	280,000	402,997	280,000	620,000
Outstanding Beginning, Weighted Average Exercise price	$ 2.91	$ 2.97	$ 2.97
Exercised, Weighted-Average Exercise Price		$ 3.33
Outstanding Ending, Weighted-Average Exercise Price	$ 2.91	$ 2.78	$ 2.91	$ 2.97
Outstanding, Weighted-Average Remaining Contractual Term	4 years 8 months 12 days	5 years 6 months	4 years 10 months 24 days	5 years 8 months 12 days
Outstanding Beginning, Aggregate Intrinsic Value	$ 5,007	$ 3,122	$ 3,122
Outstanding Ending, Aggregate Intrinsic Value	6,816	3,997	5,007	3,122
Exercisable Ending, Number of Options	260,000	369,797
Exercisable Ending , Weighted-Average Exercise Price	$ 2.65	$ 2.50
Exercisable Ending, Weighted-Average Remaining Contractual Term	4 years 4 months 24 days	5 years 2 months 12 days
Exercisable Ending, Aggregate Intrinsic Value	$ 6,397	$ 3,772