Common stock and common stock warrants (Details) $ / shares in Units, $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2022 USD ($) Vote $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Jul. 19, 2021 shares	Jun. 30, 2021 shares
Common stock and common stock warrants
Cash dividends | $	$ 0.0	$ 0.0
Shares reserved				20,268,510
Common Class A
Common stock and common stock warrants
Common stock, authorized (in shares)	210,000,000	210,000,000	210,000,000
Common stock, issued (in shares)	36,389,073	34,564,040
Common stock, outstanding (in shares)	36,389,073	34,564,040
Common stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01
Number of votes | Vote	1
Common Class B
Common stock and common stock warrants
Common stock, authorized (in shares)	10,000,000	10,000,000	10,000,000
Common stock, issued (in shares)	5,553,379	6,903,379
Common stock, outstanding (in shares)	5,553,379	6,903,379
Common stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01