Balance Sheets (Parenthetical) - $ / shares shares in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	20,000	20,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	150,000	150,000
Common stock, shares issued (in shares)	41,964	36,781
Common stock, shares outstanding (in shares)	41,964	36,781