Condensed Consolidated Statements of Stockholders Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning Balance at Dec. 31, 2018	$ 680,941	$ 1,232	$ 1,716,894	$ (1,422)	$ (1,035,763)
Balance (in shares) at Dec. 31, 2018		123,192,540
Increase (Decrease) in Stockholders' Equity
Equity component of convertible notes, net of tax and issuance costs	268,390		268,390
Shares issued to settle convertible notes (in shares)		2,158,991
Shares issued to settle convertible notes	182,435	$ 22	182,413
Settlement of convertible notes, net of tax	(300,768)		(300,768)
Exercise of common stock options	3,650	$ 2	3,648
Exercise of common stock options (in shares)		235,278
Issuance of common stock to fund the Company's 401(k) match	7,409	$ 1	7,408
Issuance of common stock to fund the Company's 401(k) match (in shares)		86,532
Compensation expense related to issuance of stock options and restricted stock awards	16,166	$ 35	16,131
Compensation expense related to issuance of stock options and restricted stock awards (in shares)		3,410,481
Issuance of common stock for business combinations	0
Net loss	(82,939)				(82,939)
Accumulated other comprehensive loss	1,656			1,656
Ending Balance at Mar. 31, 2019	776,940	$ 1,292	1,894,116	234	(1,118,702)
Balance (in shares) at Mar. 31, 2019		129,083,822
Beginning Balance at Dec. 31, 2019	$ 2,288,061	$ 1,477	3,406,440	(100)	(1,119,756)
Balance (in shares) at Dec. 31, 2019	147,625,696	147,625,696
Increase (Decrease) in Stockholders' Equity
Equity component of convertible notes, net of tax and issuance costs	$ 346,641		346,641
Shares issued to settle convertible notes (in shares)	2,159,716
Settlement of convertible notes, net of tax	$ (64,199)		(64,199)
Exercise of common stock options	4,300	$ 2	4,298
Exercise of common stock options (in shares)		160,286
Issuance of common stock to fund the Company's 401(k) match	12,007	$ 1	12,006
Issuance of common stock to fund the Company's 401(k) match (in shares)		136,559
Compensation expense related to issuance of stock options and restricted stock awards	29,560	$ 11	29,549
Compensation expense related to issuance of stock options and restricted stock awards (in shares)		1,141,376
Issuance of common stock for business combinations	$ 28,597	$ 4	28,593
Issuance of common stock for business combinations (in shares)	17,046,159	382,947
Net loss	$ (105,697)				(105,697)
Accumulated other comprehensive loss	(1,617)			(1,617)
Ending Balance at Mar. 31, 2020	$ 2,537,653	$ 1,495	$ 3,763,328	$ (1,717)	$ (1,225,453)
Balance (in shares) at Mar. 31, 2020	149,446,864	149,446,864