CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2018		34,606,760
Beginning balance at Dec. 31, 2018	$ 746,655	$ 346	$ 1,292,736	$ (3,985)	$ (542,442)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net shares issued in connection with the exercise of stock options and vesting of restricted stock units, net of withholdings (in shares)		214,868
Net shares issued in connection with the exercise of stock options and vesting of restricted stock units, net of withholdings	(1,604)	$ 2	(1,606)
Repurchase of common stock pursuant to the share repurchase program (in shares)		(1,074,800)
Repurchase of common stock pursuant to the share repurchase program	(13,730)	$ (11)	(13,719)
Non-cash equity based compensation	4,873		4,873
Unrealized (losses) gains on securities, net of tax	609			609
Net loss	(122,084)				(122,084)
Ending balance (in shares) at Mar. 31, 2019		33,746,828
Ending balance at Mar. 31, 2019	$ 614,719	$ 337	1,282,284	(3,376)	(664,526)
Beginning balance (in shares) at Dec. 31, 2019	33,999,081	33,999,081
Beginning balance at Dec. 31, 2019	$ 286,119	$ 339	1,297,917	(3,239)	(1,008,898)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net shares issued in connection with the exercise of stock options and vesting of restricted stock units, net of withholdings (in shares)		267,175
Net shares issued in connection with the exercise of stock options and vesting of restricted stock units, net of withholdings	(1,210)	$ 3	(1,213)
Non-cash equity based compensation	3,868		3,868
Unrealized (losses) gains on securities, net of tax	(548)			(548)
Net loss	$ (24,491)				(24,491)
Ending balance (in shares) at Mar. 31, 2020	34,266,256	34,266,256
Ending balance at Mar. 31, 2020	$ 263,738	$ 342	$ 1,300,572	$ (3,787)	$ (1,033,389)