Recent Accounting Pronouncements - Additional Information (Details)						1 Months Ended	3 Months Ended		9 Months Ended
	Dec. 25, 2019 $ / d	Dec. 09, 2018 t $ / d	May 04, 2018 t $ / d	Apr. 28, 2017 t $ / d	Oct. 15, 2015 USD ($)	Nov. 30, 2018 USD ($)	Sep. 30, 2020 USD ($) t	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) contract t	Sep. 30, 2019 USD ($)	Jul. 27, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of contracts | contract									5
Dead weight tonnage of operating fleet | t							2,893,767		2,893,767
Fair value below contract value of time charters acquired														$ 1,800,000
Increase to lease liability												$ 4,500,000
Operating lease right-of-use assets							$ 10,669,431		$ 10,669,431			20,410,037	$ 20,410,037
Operating lease, liability							11,642,230		11,642,230
Cash paid on operating leases							$ 2,900,000	$ 3,700,000	$ 9,900,000	$ 11,200,000
Weighted average remaining lease term							12 years 7 months 6 days		12 years 7 months 6 days
Revenue earned as demurrage							$ 68,182,301	74,110,376	$ 199,952,404	220,891,288
Deferred costs							300,000		300,000
Allowance for credit loss							2,300,000		2,300,000			$ 2,500,000
Voyage In Progress
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue earned as demurrage							600,000	$ 1,800,000	$ 4,600,000	$ 7,800,000
Letter of Credit
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted cash, cash equivalents					$ 74,917						$ 74,917
Chartered-in contracts greater than 12 months
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of contracts | contract									3
Operating lease right-of-use assets							9,171,817		$ 9,171,817				18,442,965
Operating lease, liability							10,151,384		$ 10,151,384
2013 Built Japanese Vessel
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Dead weight tonnage of operating fleet | t				61,400
Charters agreement term				4 years
Charters agreement term, extension option				2 years
2013 Built Japanese Vessel | First Four Years
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d				12,800
2013 Built Japanese Vessel | First Optional Year
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d				13,800
2013 Built Japanese Vessel | Second Optional Year
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d				14,300
2013 Built Ultramax Vessel
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Dead weight tonnage of operating fleet | t			61,425
Charters agreement term			3 years
Charters agreement term, extension option			2 years
2013 Built Ultramax Vessel | First Optional Year
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d			13,750
2013 Built Ultramax Vessel | Second Optional Year
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d			14,750
2013 Built Ultramax Vessel | First Three Years
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d			12,700
2016 Built Ultramax Vessel
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Dead weight tonnage of operating fleet | t		62,487
Charters agreement term		2 years
2016 Built Ultramax Vessel | First Two Years
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d	11,600	14,250
2016 Built Ultramax Vessel | Third Year Option
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Vessel hiring rate (in dollars per day) | $ / d		15,250
Office leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of contracts | contract									2
Operating lease right-of-use assets							1,497,614		$ 1,497,614				$ 1,967,072
Operating lease, liability							$ 1,490,846		$ 1,490,846
Office leases | Lease Agreement for Office Space in Stamford
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Average annual rent expense					$ 400,000
Office leases | Singapore Lease Arrangement
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Average annual rent expense						$ 300,000
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, term of contract							30 days		30 days
Incremental borrowing rate							5.05%		5.05%
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, term of contract							2 years		2 years
Incremental borrowing rate							6.08%		6.08%