Stock-based Compensation - Outstanding and Exercisable Stock Options, By Exercise Price (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Jan. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price (in dollars per share)		$ 9.41	$ 9.41	$ 9.41
Outstanding, Options (in shares)	6,296,789
Outstanding, Weighted-Average Remaining Contractual Term	7 years 8 months 12 days
Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 9.30
Exercisable, Options (in shares)	4,648,885
Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 6.64
Exercise Price Range One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price (in dollars per share)	$ 6.64
Outstanding, Options (in shares)	5,044,408
Outstanding, Weighted-Average Remaining Contractual Term	7 years 2 months 12 days
Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 6.64
Exercisable, Options (in shares)	4,648,885
Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 6.64
Exercise Price Range Two [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise Price (in dollars per share)	$ 20.00
Outstanding, Options (in shares)	1,252,381
Outstanding, Weighted-Average Remaining Contractual Term	9 years 6 months
Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 20.00
Exercisable, Options (in shares)	0
Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 0.00