Vessels - Vessel and Vessel Improvements (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Movement in Property, Plant and Equipment [Roll Forward]
Vessels and vessel improvements, beginning balance	$ 567,592,950
Vessels and vessel improvements, ending balance	697,713,444	$ 567,592,950
Vessels and Vessel Improvements
Movement in Property, Plant and Equipment [Roll Forward]
Vessels and vessel improvements, beginning balance	567,592,950
Advance paid for purchase of Singapore Eagle at December 31, 2016		1,926,886
Purchase of Vessels and Vessel Improvements	174,004,286
Sale of vessel	(7,611,013)
Transfer to Vessels held for sale	(16,915,287)
Vessel depreciation expense	(21,284,378)
Vessels and vessel improvements, ending balance	$ 697,713,444	$ 567,592,950