Consolidated Statements of Changes in Redeemable Noncontrolling Interest and Stockholders' Deficit - USD ($) $ in Thousands	Total	Redeemable Noncontrolling Interest [Member]	Class A Common Stock [Member]	Class B Common Stock [Member]	Common Stock [Member] Class A Common Stock [Member]	Common Stock [Member] Class B Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2018	$ (82,853)				$ 203	$ 232	$ 150,595	$ (233,883)
Beginning balance, redeemable noncontrolling interest at Dec. 31, 2018		$ 62,482
Beginning balance, shares at Dec. 31, 2018					20,347,065	23,094,221
Net loss	(13,044)	(8,894)						(13,044)
Share-based compensation	1,518						1,518
Issuance of Class A Common Stock under registered direct offering	5,443				$ 37		5,406
Issuance of Class A Common Stock under registered direct offering, shares					3,636,364
Issuance of Class A Common Stock to a related party under the Letter Agreements	27,500				$ 169		27,331
Issuance of Class A Common Stock to a related party under the Letter Agreements, shares					16,923,427
Issuance of Letter Agreement and warrants to purchase Class A Common Stock - related party	(992)						(992)
Vesting of restricted stock units, shares					11,666
Change in redemption value of noncontrolling interest		(13,405)
Change in redemption value of noncontrolling interest	13,405							13,405
Ending balance at Dec. 31, 2019	(49,023)				$ 409	$ 232	183,858	(233,522)
Ending balance, redeemable noncontrolling interest at Dec. 31, 2019		40,183
Ending balance, shares at Dec. 31, 2019					40,918,522	23,094,221
Net loss	(8,499)	(4,303)						(8,499)
Share-based compensation	1,009						1,009
Issuance of Class A Common Stock under ATM offering	12,496				$ 55		12,441
Issuance of Class A common stock under ATM offering shares					5,480,941
Issuance of Class A Common Stock to a related party under the Letter Agreements	10,000				$ 63		9,937
Issuance of Class A Common Stock to a related party under the Letter Agreements, shares					6,250,000
Issuance of Class A Common Stock under LPC Agreement	1,930				$ 14		1,916
Issuance of Class A Common Stock under LPC agreement shares					1,389,580
Vesting of restricted stock units, shares					11,667
Change in redemption value of noncontrolling interest		48,015
Change in redemption value of noncontrolling interest	(48,015)							(48,015)
Ending balance at Dec. 31, 2020	(80,102)				$ 541	$ 232	209,161	(290,036)
Ending balance, redeemable noncontrolling interest at Dec. 31, 2020	83,895	83,895
Ending balance, shares at Dec. 31, 2020			54,050,710	23,094,221	54,050,710	23,094,221
Net loss	(12,987)	(4,744)						(12,987)
Share-based compensation	2,356						2,356
Issuance of Class A Common Stock under ATM offering	17,670				$ 89		17,581
Issuance of Class A common stock under ATM offering shares					8,929,147
Exchange of Class B Common Stock for Class A Common Stock, shares					361	(361)
Exercise of stock options	$ 47						47
Exercise of stock options, shares	20,833				20,833
Issuance of Class A Common Stock under LPC Agreement	$ 9,087				$ 39		9,048
Issuance of Class A Common Stock under LPC agreement shares					3,941,726
Change in redemption value of noncontrolling interest		(54,189)
Change in redemption value of noncontrolling interest	54,189							54,189
Ending balance at Dec. 31, 2021	(9,740)				$ 669	$ 232	$ 238,193	$ (248,834)
Ending balance, redeemable noncontrolling interest at Dec. 31, 2021	$ 24,962	$ 24,962
Ending balance, shares at Dec. 31, 2021			66,942,777	23,093,860	66,942,777	23,093,860