UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE SERIES A-1 PREFERRED STOCK, CONVERTIBLE AND REDEEMABLE SERIES A-2 PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Redeemable Series A-1 Preferred Stock	Convertible And Redeemable Series A-2 Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Notes Receivable from Stockholders	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2018	$ 6,900				$ 47,869	$ (40,847)	$ (122)
Beginning balance, shares at Dec. 31, 2018				8,137,771
Beginning balance at Dec. 31, 2018		$ 109,206
Beginning balance, shares at Dec. 31, 2018		12,000
Net income (loss)	(5,242)					(5,242)
Accretion of the redeemable series A-1 preferred stock to redeemable value	(4,534)				(4,534)
Accretion of the redeemable series A-1 preferred stock to redeemable shares		$ 4,534
Stock-based compensation	1,228				1,228
Common stock issued	6				6
Common stock issued, shares				1,775
Ending balance at Mar. 31, 2019	(1,642)				44,569	(46,089)	(122)
Ending balance, shares at Mar. 31, 2019				8,139,546
Ending balance at Mar. 31, 2019		$ 113,740
Ending balance, shares at Mar. 31, 2019		12,000
Beginning balance at Dec. 31, 2018	6,900				47,869	(40,847)	(122)
Beginning balance, shares at Dec. 31, 2018				8,137,771
Beginning balance at Dec. 31, 2018		$ 109,206
Beginning balance, shares at Dec. 31, 2018		12,000
Net income (loss)	(12,247)
Accumulated other comprehensive income (loss)	3
Ending balance at Sep. 30, 2019	(11,922)				41,291	(53,094)	(122)	$ 3
Ending balance, shares at Sep. 30, 2019				8,310,885
Ending balance at Sep. 30, 2019		$ 123,547
Ending balance, shares at Sep. 30, 2019		12,000
Beginning balance at Mar. 31, 2019	(1,642)				44,569	(46,089)	(122)
Beginning balance, shares at Mar. 31, 2019				8,139,546
Beginning balance at Mar. 31, 2019		$ 113,740
Beginning balance, shares at Mar. 31, 2019		12,000
Net income (loss)	(322)					(322)
Accretion of the redeemable series A-1 preferred stock to redeemable value	(4,777)				(4,777)
Accretion of the redeemable series A-1 preferred stock to redeemable shares		$ 4,777
Stock-based compensation	1,294				1,294
Common stock issued	3,452				3,452
Common stock issued, shares				138,781
Accumulated other comprehensive income (loss)	23							23
Ending balance at Jun. 30, 2019	(1,972)				44,538	(46,411)	(122)	23
Ending balance, shares at Jun. 30, 2019				8,278,327
Ending balance at Jun. 30, 2019		$ 118,517
Ending balance, shares at Jun. 30, 2019		12,000
Net income (loss)	(6,683)					(6,683)
Accretion of the redeemable series A-1 preferred stock to redeemable value	(5,030)				(5,030)
Accretion of the redeemable series A-1 preferred stock to redeemable shares		$ 5,030
Stock-based compensation	1,055				1,055
Common stock issued	728				728
Common stock issued, shares				32,558
Accumulated other comprehensive income (loss)	(20)							(20)
Ending balance at Sep. 30, 2019	(11,922)				41,291	(53,094)	$ (122)	3
Ending balance, shares at Sep. 30, 2019				8,310,885
Ending balance at Sep. 30, 2019		$ 123,547
Ending balance, shares at Sep. 30, 2019		12,000
Beginning balance at Dec. 31, 2019	(26,291)				38,153	(64,404)		(40)
Beginning balance, shares at Dec. 31, 2019				8,370,107
Beginning balance at Dec. 31, 2019		$ 128,822
Beginning balance, shares at Dec. 31, 2019		12,000	0
Net income (loss)	(41,248)					(41,248)
Accretion of the redeemable series A-1 preferred stock to redeemable value	(5,415)				(5,415)
Accretion of the redeemable series A-1 preferred stock to redeemable shares		$ 5,415
Stock-based compensation	1,150				1,150
Accumulated other comprehensive income (loss)	37							37
Ending balance at Mar. 31, 2020	(71,767)				33,888	(105,652)		(3)
Ending balance, shares at Mar. 31, 2020				8,370,107
Ending balance at Mar. 31, 2020		$ 134,237
Ending balance, shares at Mar. 31, 2020		12,000
Beginning balance at Dec. 31, 2019	(26,291)				38,153	(64,404)		(40)
Beginning balance, shares at Dec. 31, 2019				8,370,107
Beginning balance at Dec. 31, 2019		$ 128,822
Beginning balance, shares at Dec. 31, 2019		12,000	0
Net income (loss)	$ (58,761)
Redemption of the series A-1, shares	1,786,739
Dividend payment to the series A-2 preferred shareholders			$ (2,900)
Cancellation of shares	(117,785)
Accumulated other comprehensive income (loss)	$ 27
Ending balance at Sep. 30, 2020	138,767				261,945	(123,165)		(13)
Ending balance, shares at Sep. 30, 2020				24,893,122
Ending balance at Sep. 30, 2020			$ 152,928
Ending balance, shares at Sep. 30, 2020		0	17,500
Beginning balance at Mar. 31, 2020	(71,767)				33,888	(105,652)		(3)
Beginning balance, shares at Mar. 31, 2020				8,370,107
Beginning balance at Mar. 31, 2020		$ 134,237
Beginning balance, shares at Mar. 31, 2020		12,000
Net income (loss)	13,224					13,224
Accretion of the redeemable series A-1 preferred stock to redeemable value	(5,644)				(5,644)
Accretion of the redeemable series A-1 preferred stock to redeemable shares		$ 5,644
Issuance of the convertible and redeemable series A-2 preferred stock			$ 152,928
Issuance of the convertible and redeemable series A-2 preferred stock, shares			17,500
Stock-based compensation	1,140				1,140
Common stock issued	25,021				25,021
Common stock issued, shares				794,639
Accumulated other comprehensive income (loss)	(90)							(90)
Ending balance at Jun. 30, 2020	(38,116)				54,405	(92,428)		(93)
Ending balance, shares at Jun. 30, 2020				9,164,746
Ending balance at Jun. 30, 2020		$ 139,881	$ 152,928
Ending balance, shares at Jun. 30, 2020		12,000	17,500
Net income (loss)	(30,737)					(30,737)
Accretion of the redeemable series A-1 preferred stock to redeemable value	6,542				(6,542)
Accretion of the redeemable series A-1 preferred stock to redeemable shares		$ 6,542
Series A-1 preferred stock deemed dividend	(24,341)				(24,341)
Series A-1 preferred stock deemed dividend		$ 24,341
Redemption of the series A-1	$ 26,801				26,801
Temporary equity redemption of the series A-1, shares		(12,000)
Temporary equity redemption of the series A-1, value		$ (170,764)
Redemption of the series A-1, shares	1,786,739			1,786,739
Dividend payment to the series A-2 preferred shareholders	$ (2,870)		$ (2,900)		(2,870)
Exercise of the series A-1 preferred stock warrant	11,871				11,871
Exercise of the series A-1 preferred stock warrant, shares				534,240
Exercise of the series A-2 preferred stock warrant	44,441				44,441
Exercise of the series A-2 preferred stock warrant,shares				1,999,999
Stock-based compensation	1,149				1,149
Common stock issued	150				150
Common stock issued, shares				26,850
Issuance of common stock in connection with initial public offering, net of issuance costs of $15.6 million	$ 156,881				156,881
Issuance of common stock in connection with initial public offering, net of issuance costs of $15.6 million, shares				11,500,000
Cancellation of shares	(117,785)			(119,452)
Accumulated other comprehensive income (loss)	$ 80							80
Ending balance at Sep. 30, 2020	$ 138,767				$ 261,945	$ (123,165)		$ (13)
Ending balance, shares at Sep. 30, 2020				24,893,122
Ending balance at Sep. 30, 2020			$ 152,928
Ending balance, shares at Sep. 30, 2020		0	17,500