Subsequent events (Details) $ in Millions	May 06, 2022 defendant	May 02, 2022 USD ($)	May 01, 2022 USD ($)	Mar. 30, 2022 defendant
Officer
Subsequent Event [Line Items]
Number of defendants				1
Former Officer
Subsequent Event [Line Items]
Number of defendants				1
Subsequent Event
Subsequent Event [Line Items]
Required deposits | $		$ 3.3	$ 3.3
Escrow deposits for covenants satisfaction | $		$ 3.3
Subsequent Event | Officer
Subsequent Event [Line Items]
Number of defendants	1
Subsequent Event | Former Officer
Subsequent Event [Line Items]
Number of defendants	1