Equity-Based Compensation Plans (Details 1) (USD $)	3 Months Ended
	Mar. 31, 2014
Summary of stock option activity
Number of options, Beginning balance	4,005,589
Weighted Average Exercise Price, Beginning balance	$ 15.40
Number of Options, Granted	735,500
Weighted Average Exercise Price, Granted	$ 10.89
Number of Options, Exercised	(7,334)
Weighted Average Exercise Price, Exercised	$ 5.86
Number of Options, Cancelled	(307,741)
Weighted Average Exercise Price, Cancelled	$ 21.18
Number of options, Ending balance	4,426,014
Weighted Average Exercise Price, Ending balance	$ 14.27
Weighted Average Remaining Contractual Life-Years	4 years 8 months
Aggregate intrinsic value, Ending balance	$ 3,762,925
Number of Options, Exercisable options	2,702,748
Weighted Average Exercise Price, Exercisable options	$ 17.25
Weighted Average Remaining Contractual Term, Exercisable options	3 years 9 months
Aggregate Intrinsic Value, Exercisable options	2,383,645
Number of Options, Expected to vest	1,621,640
Weighted Average Exercise Price, Expected to vest options	$ 9.53
Weighted Average Remaining Contractual Term, Expected to vest options	6 years
Aggregate Intrinsic Value, Expected to vest	$ 1,368,799