Accounting policies (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Cash and cash equivalents	$ 5,100,000		$ 5,100,000		$ 7,400,000
Deposits held in foreign bank	10,100,000		10,100,000
Foreign Currency Transaction Gain (Loss), before Tax [Abstract]
Foreign Currency Transaction Gain (Loss), before Tax	$ 24,397,000	$ 6,988,000	$ 50,176	$ 29,034
Bahamas [Member]
Deposits held in foreign bank					$ 5,700,000