Consolidated Balance Sheets (Parenthetical) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	60,000,000	200,000,000
Common stock, shares issued	15,387,000	3,762,000
Common stock, shares outstanding	15,387,000	3,762,000
Convertible preferred stock
Convertible preferred stock, par value	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized	0	130,100,000
Convertible preferred stock, shares issued	0	8,148,000
Convertible preferred stock, shares outstanding	0	8,148,000
Convertible preferred stock, liquidation preference	$ 0	$ 48,954,000