Derivative Instruments and Fair Value Measurements - Derivative Instruments Not Designated As Hedging Instruments (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, location of (gain)/loss recognized	$ 647,457	$ 163,499	$ (138,206)	$ 464,284
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, balance sheet location, total	(126,651)		(126,651)		$ 0
Forward Freight Agreements | Other Current Assets
Derivative Instruments, Gain (Loss) [Line Items]
Collateral related to derivative instruments under collateral security arrangements	1,154,331		1,154,331		0
Forward Freight Agreements | Not Designated as Hedging Instrument | Fair Value of Derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, balance sheet location, fair value of derivatives	(281,266)		(281,266)		0
Forward Freight Agreements | Other Expense
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, location of (gain)/loss recognized	862,224	163,499	73,509	464,284
Bunker Swaps | Not Designated as Hedging Instrument | Other Current Assets
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, balance sheet location, other current assets	154,615		154,615		$ 0
Bunker Swaps | Other Expense
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives not designated as hedging instruments, location of (gain)/loss recognized	$ (214,767)	$ 0	$ (211,715)	$ 0