CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit
Beginning Balance at Dec. 31, 2018	$ 11,015	$ 1	$ 58,431	$ (47,417)
Beginning Balance, Shares at Dec. 31, 2018		10,000
Net (loss) income	(7,240)			(7,240)
Ending Balance at Sep. 30, 2019	3,775	$ 1	58,431	(54,657)
Ending Balance, Shares at Sep. 30, 2019		10,000
Beginning Balance at Jun. 30, 2019	2,696	$ 1	58,431	(55,736)
Beginning Balance, Shares at Jun. 30, 2019		10,000
Net (loss) income	1,079			1,079
Ending Balance at Sep. 30, 2019	3,775	$ 1	58,431	(54,657)
Ending Balance, Shares at Sep. 30, 2019		10,000
Beginning Balance at Dec. 31, 2019	$ 62,140	$ 2	116,162	(54,024)
Beginning Balance, Shares at Dec. 31, 2019	14,968	14,968
Stock-based compensation expense	$ 9,749		9,749
Net (loss) income	(11,363)			(11,363)
Issuance of common stock upon follow-on public offering net of underwriting discounts and commissions and other offering costs	45,789		45,789
Issuance of common stock upon follow-on public offering net of underwriting discounts and commissions and other offerings costs, Shares		1,525
Issuance of shares upon vesting of restricted stock units, net of tax withholdings	(3,492)		(3,492)
Issuance of shares upon vesting of restricted stock units, net of tax withholdings, Shares		447
Ending Balance at Sep. 30, 2020	$ 102,823	$ 2	168,208	(65,387)
Ending Balance, Shares at Sep. 30, 2020	16,940	16,940
Beginning Balance at Jun. 30, 2020	$ 99,569	$ 2	164,287	(64,720)
Beginning Balance, Shares at Jun. 30, 2020		16,716
Stock-based compensation expense	3,919		3,919
Net (loss) income	(667)			(667)
Issuance of shares upon vesting of restricted stock units, net of tax withholdings	2		2
Issuance of shares upon vesting of restricted stock units, net of tax withholdings, Shares		224
Ending Balance at Sep. 30, 2020	$ 102,823	$ 2	$ 168,208	$ (65,387)
Ending Balance, Shares at Sep. 30, 2020	16,940	16,940