Segment information - Property, plant and equipment, net by major geographic region (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Net	$ 52,946,539	$ 57,687,984
Cayman Islands [Member]
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Net	26,687,944	28,474,748
Bahamas [Member]
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Net	24,004,707	26,975,427
United States [Member]
Segment Reporting Information [Line Items]
Property, Plant and Equipment, Net	$ 2,253,888	$ 2,237,809

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Name:	us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant