Equity Summary of Unvested Stock Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Shares
Unvested, beginning of period (in shares)	7,193,577
Granted (in shares)	75,100
Cancelled (in shares)	(239,322)
Vested (in shares)	(3,961,420)
Unvested, end of period (in shares)	3,067,935	7,193,577
Weighted- Average Grant Date Fair Value
Unvested, beginning of period (in dollars per share)	$ 3.08
Granted (in dollars per share)	5.15	$ 4.18	$ 3.08
Cancelled (in dollars per share)	3.79
Vested (in dollars per share)	2.53
Unvested, end of period (in dollars per share)	$ 3.81	$ 3.08