Equity (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Class of Stock [Line Items]
Common stock shares authorized under equity program	500,000,000	500,000,000	500,000,000	500,000,000	500,000,000
Net proceeds *			$ (149,000)	$ 54,649,000
At-the-market offering
Class of Stock [Line Items]
Common stock shares authorized under equity program	6,400,000		6,400,000
Common stock shares reserved for future issuance	3,600,000		3,600,000
Shares issued	0	1,100,000	0	1,800,000
Net proceeds *	$ 0	$ 34,900,000	$ (100,000)	$ 54,600,000
Issuance costs	$ 22,000	$ 443,000	$ 149,000	$ 743,000