Statements of Cash Flows (Unaudited) (Parenthetical) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Statement Of Cash Flows [Abstract]
Change in fair value of warrant liabilities related party	$ 0	$ 59,031
Change in fair value of convertible promissory notes related party	0	1,053
Related parties prepaid expenses and other assets current	0	17
Related parties accounts payable and accrued expenses	238	186
Related parties accrued interest	$ 0	$ 483