Share-Based Compensation - Summary of Stock Option Activity (Details) - Stock options shares in Thousands	3 Months Ended
	Mar. 31, 2020 $ / shares shares
Number of Shares Underlying Options
Outstanding, beginning balance (in shares) | shares	6,780
Granted (in shares) | shares	105
Exercised (in shares) | shares	(49)
Forfeited (in shares) | shares	(201)
Outstanding, ending balance (in shares) | shares	6,635
Vested and exercisable, September 30, 2019 (in shares) | shares	3,482
Vested and expected to vest, September 30. 2019 (in shares) | shares	6,383
Weighted Average Exercise Price
Outstanding, beginning balance (in dollars per share) | $ / shares	$ 10.89
Granted (in dollars per share) | $ / shares	6.58
Exercised (in dollars per share) | $ / shares	2.78
Forfeited (in dollars per share) | $ / shares	17.36
Outstanding, ending balance (in dollars per share) | $ / shares	10.69
Vested and exercisable, September 30, 2019 (in dollars per share) | $ / shares	17.07
Vested and expected to vest, September 30. 2019 (in dollars per share) | $ / shares	$ 10.97