Share-Based Compensation - Stock Option Activity (Details) - $ / shares	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Options
Outstanding at beginning of period (in shares)	10,680,340
Granted (in shares)	7,602
Exercised (in shares)	(553,520)
Canceled/forfeited (in shares)	(61,766)
Expired (in shares)	(1,176,000)
Outstanding at end of period (in shares)	8,896,656
Outstanding, vested and exercisable at end of period (in shares)	6,362,802	7,868,280
Weighted- Average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 5.59
Granted (in dollars per share)	12.69
Exercised (in dollars per share)	5.53
Canceled/forfeited (in dollars per share)	2.46
Expired (in dollars per share)	14.71
Outstanding at end of period (in dollars per share)	4.41
Outstanding, vested and exercisable at end of period (in dollars per share)	$ 5.04	$ 6.57