Stock Options - Summary of Stock Options by Exercise Price Range (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Number of Options	4,310,000		4,310,000
Outstanding Weighted Average Remaining Contractual Term (in years)			5 years 4 months 21 days
Outstanding Weighted Average Exercise Price (per share)	$ 9.38		$ 9.38
Exercisable Number of Options	3,696,669		3,696,669
Exercisable Weighted Average Exercise Price (per share)	$ 8.54		$ 8.54
Stock-based compensation	$ 848	$ 1,172	$ 1,913	$ 1,956
$3.40 - $3.95
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock options exercise price range, lower limit			$ 3.40
Stock options exercise price range, upper limit			$ 3.95
Outstanding Number of Options	1,900,000		1,900,000
Outstanding Weighted Average Remaining Contractual Term (in years)			3 years 2 months 12 days
Outstanding Weighted Average Exercise Price (per share)	$ 3.66		$ 3.66
Exercisable Number of Options	1,900,000		1,900,000
Exercisable Weighted Average Exercise Price (per share)	$ 3.66		$ 3.66
$5.81 - $14.36
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock options exercise price range, lower limit			5.81
Stock options exercise price range, upper limit			$ 14.36
Outstanding Number of Options	1,390,000		1,390,000
Outstanding Weighted Average Remaining Contractual Term (in years)			7 years 1 month 10 days
Outstanding Weighted Average Exercise Price (per share)	$ 10.86		$ 10.86
Exercisable Number of Options	1,110,002		1,110,002
Exercisable Weighted Average Exercise Price (per share)	$ 11.03		$ 11.03
$17.10 - $20.51
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Stock options exercise price range, lower limit			17.10
Stock options exercise price range, upper limit			$ 20.51
Outstanding Number of Options	1,020,000		1,020,000
Outstanding Weighted Average Remaining Contractual Term (in years)			7 years 1 month 21 days
Outstanding Weighted Average Exercise Price (per share)	$ 18.01		$ 18.01
Exercisable Number of Options	686,667		686,667
Exercisable Weighted Average Exercise Price (per share)	$ 18.01		$ 18.01