Condensed Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Class A Common Stock, Class B Common Stock and Class C Capital Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning Balance at Dec. 31, 2018	$ 3,267,179	$ 21	$ 3,939,842	$ (671,779)	$ (905)
Beginning Balance (in shares) at Dec. 31, 2018		203,904,265,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common and capital stock upon exercise of stock options	13,564		13,564
Issuance of common and capital stock upon exercise of stock options (in shares)		729,788,000
Vesting of restricted stock units (in shares)		496,347,000
Shares and value of restricted stock units withheld for tax liability	(2)		(2)
Shares and value of restricted stock units withheld for tax liability (in shares)		(68,000)
Share-based compensation expense	68,814		68,814
Net loss	(67,525)			(67,525)
Other comprehensive income (loss)	1,102				1,102
Ending Balance at Mar. 31, 2019	3,283,132	$ 21	4,022,218	(739,304)	197
Ending Balance (in shares) at Mar. 31, 2019		205,130,332,000
Beginning Balance at Dec. 31, 2019	3,435,421	$ 21	4,412,200	(977,140)	340
Beginning Balance (in shares) at Dec. 31, 2019		209,066,855,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common and capital stock upon exercise of stock options	$ 92,202	$ 1	92,201
Issuance of common and capital stock upon exercise of stock options (in shares)	3,207,375	3,207,375,000
Vesting of restricted stock units (in shares)		638,909,000
Share-based compensation expense	$ 47,465		47,465
Net loss	(163,273)			(163,273)
Other comprehensive income (loss)	3,946				3,946
Ending Balance at Mar. 31, 2020	$ 3,415,761	$ 22	$ 4,551,866	$ (1,140,413)	$ 4,286
Ending Balance (in shares) at Mar. 31, 2020		212,913,139,000