Consolidated Statements of Convertible Redeemable Preferred Stock, Redeemable Noncontrolling Interest, Stockholders' Deficit and Noncontrolling Interest - USD ($) $ in Thousands		Total	Total Stockholders' Equity (Deficit)	Total Stockholders' Equity (Deficit) Cumulative effect upon adoption of new accounting standard	Convertible Redeemable Preferred Stock	Redeemable Noncontrolling  Interest	Common Stock		Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Accumulated Deficit Cumulative effect upon adoption of new accounting standard	Noncontrolling Interest	Noncontrolling Interest Cumulative effect upon adoption of new accounting standard	Class A common stock	Class A common stock Total Stockholders' Equity (Deficit)	Class A common stock Common Stock		Class A common stock Additional Paid-In Capital	Class B common stock	Class B common stock Total Stockholders' Equity (Deficit)	Class B common stock Common Stock		Class B common stock Additional Paid-In Capital
Beginning balance (in shares) at Dec. 31, 2017					71,740,162		10,353,269	[1]
Beginning balance at Dec. 31, 2017			$ (2,199,921)		$ 1,465,841	$ 58,154	$ 1	[1],[2]	$ 150,804	$ (162)	$ (2,350,564)		$ 155,372
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock upon public offering, net (in shares)	[1]																20,700,000
Issuance of Class A common stock upon public offering, net																$ 282,276	$ 2	[1]	$ 282,274
Issuance of common stock (in shares)	[1]						166,667															5,734,440
Issuance of common stock			2,500						2,500												$ 221,580	$ 1	[1]	$ 221,579
Issuance of common stock upon exercise of warrants (in shares)	[1]						312,575
Conversion of notes (in shares)					(71,740,162)		71,740,162	[1]
Conversion of Notes			1,465,841		$ (1,465,841)		$ 7	[1]	1,465,834				0
Reclassification of redeemable convertible preferred stock warrant liability to additional paid-in capital		$ 882	882						882
Reclassification of derivative liability into additional paid-in capital (as restated)			177,963						177,963
Issuance of restricted stock awards (in shares)	[1]						17,793
Issuance of restricted stock awards			349						349
Exercise of stock options (in shares)	[1]						396,277
Exercise of stock options			1,521						1,521
Stock-based compensation			177,646						177,646
Unrealized loss on available-for-sale securities		26	26							26
Change in effective portion of interest rate swap agreement		2,098	267			2				267			1,829
Distributions to noncontrolling interests			0			(6,788)							(8,462)
Net loss		(291,276)	(273,540)			5,893					(273,540)		(23,629)
Ending balance (in shares) at Dec. 31, 2018					0		109,421,183	[1]
Ending balance at Dec. 31, 2018			(142,610)		$ 0	57,261	$ 11	[1]	2,481,352	131	(2,624,104)		125,110
Ending balance (Accounting Standards Update 2014-09) at Dec. 31, 2018				$ (17,996)								$ (17,996)
Ending balance (Accounting Standards Update 2017-12) at Dec. 31, 2018				$ 130								$ 130		$ (130)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock			0
Conversion of notes (in shares)	[1]						616,302
Conversion of Notes			6,933						6,933
Reclassification of redeemable convertible preferred stock warrant liability to additional paid-in capital		0
Issuance of restricted stock awards (in shares)	[1]						8,921,807
Issuance of restricted stock awards			1				$ 1	[1]	0
ESPP purchase (in shares)	[1]						1,718,433
ESPP purchase			11,183						11,183
Exercise of stock options (in shares)	[1]						358,564
Exercise of stock options			1,529						1,529
Stock-based compensation			188,114						188,114
Unrealized loss on available-for-sale securities		14	14							14
Change in effective portion of interest rate swap agreement		(6,085)	(295)							(295)			(5,790)
Distributions to noncontrolling interests			102			(4,011)			102				(5,970)
Mandatory redemption of noncontrolling interests			(2,285)			(55,684)			(2,454)	169
Net loss		(323,466)	(304,414)			2,877					(304,414)		(21,929)
Ending balance (in shares) at Dec. 31, 2019					0		121,036,289	[1]							84,549,511					36,486,778
Ending balance at Dec. 31, 2019			(259,594)		$ 0	443	$ 12	[1]	2,686,759	19	(2,946,384)		91,291
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of notes (in shares)	[1]						35,881,250
Conversion of Notes			300,852				$ 4		300,848				0
Issuance of convertible notes			126,799						126,799
Adjustment of embedded derivative for debt modification			(24,071)						(24,071)
Reclassification of redeemable convertible preferred stock warrant liability to additional paid-in capital		0
Issuance of restricted stock awards (in shares)	[1]						7,806,038
Issuance of restricted stock awards			1				$ 1	[1]					0
ESPP purchase (in shares)	[1]						1,937,825
ESPP purchase			8,499						8,499				0
Exercise of stock options (in shares)	[1]						1,341,324
Exercise of stock options			14,988						14,988				0
Stock-based compensation			68,931						68,931				0
Unrealized loss on available-for-sale securities		(23)	(23)							(23)			0
Change in effective portion of interest rate swap agreement		(6,896)	(5)							(5)			(6,891)
Distributions to noncontrolling interests			0			(45)			0				(7,205)
Contribution from noncontrolling interest		6,513
Net loss		$ (179,087)	(157,553)			(21)					(157,553)		(21,513)
Ending balance (in shares) at Dec. 31, 2020					0		168,002,726	[1]							140,094,633					27,908,093
Ending balance at Dec. 31, 2020			$ 78,824		$ 0	$ 377	$ 17	[1]	$ 3,182,753	$ (9)	$ (3,103,937)		$ 62,195

[1] Common Stock issued and converted to Class A Common and Class B Common effective July 2018

[2] Common Stock issued and converted to Class A Common and Class B Common effective July 2018.