Crew management fee per month per vessel.

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Management fee per day per vessel.

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Management fee per day per vessel under bareboat charter.

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Proceeds From Unconsolidated Joint Ventures And Subsidiaries Classified As Financing Activities

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Sales and purchase broker commission fee percentage.

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Vessel brokerage commission percentage.

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Transactions With Related Parties - Additional Information (Detail)			6 Months Ended	12 Months Ended
	Jan. 25, 2016 EUR (€)	May 26, 2014 EUR (€)	Jun. 30, 2017 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Related Party Transaction [Line Items]
Due to related parties, current, total				$ 7,043,121	$ 7,930,642
Revenue from related parties						$ 1,973,643
Equity Method Investment Ownership Percentage				50.10%
Proceeds From Unconsolidated Joint Ventures And Subsidiaries Classified As Financing Activities				$ 4,958,250
Term Of Contract			5 years
Monthly Rate Of Lease Rentals			$ 337,250
The Manager [Member]
Related Party Transaction [Line Items]
Management fee, per day, per vessel				440
Management fee, per day, per vessel, under bareboat charter				$ 125
Vessel brokerage commission percentage				1.25%	1.25%	1.25%
Crew management fee, per month, per vessel					$ 2,500
Sales and purchase broker commission fee, percentage				1.00%
Due to related parties, current, total				$ 2,084,871	7,930,642
The Manager [Member] \| Additional Charge Per Day When Visits Exceed Five Days In Twelve Month Period [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				500
The Manager [Member] \| Commission Fees Incurred And Capitalized To The Cost Of Vessels [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				0	1,598,858	$ 525,978
The Manager [Member] \| Voyage Expenses Related Party [Member] \| Brokerage Commission Fees [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				1,788,543	2,037,917	1,912,505
The Manager [Member] \| Management Fees Related Party [Member] \| Management Fees [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				5,730,910	7,027,195	7,205,490
The Manager [Member] \| Vessels Operating Expenses Related Party [Member] \| Superintendent Fees [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				104,000	137,000	125,500
The Manager [Member] \| Vessels Operating Expenses Related Party [Member] \| Amounts Paid in Connection to Charter Agreements for the Vessels Operating Expense [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				0	0	675,408
The Manager [Member] \| Vessels Operating Expenses Related Party [Member] \| Crew Management Fees [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				862,500	377,500
The Manager [Member] \| Net Gain on Sale of Vessels [Member] \| Commission Expense Related to the Sale and Leaseback of Vessels [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				109,000	184,000	119,900
The Manager [Member] \| General and Administrative Expense [Member] \| Reimbursed Compensation [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				1,118,491	1,210,036	1,127,307
The Manager [Member] \| General and Administrative Expense [Member] \| Office Space Rent [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				87,192	84,686	82,192
The Manager [Member] \| Impairment Loss [Member] \| Commission Expense Related to the Sale and Leaseback of Vessels [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party					212,650
Emihar Petroleum Inc [Member]
Related Party Transaction [Line Items]
Revenue from related parties				0	0	1,973,643
Brave [Member] \| Vessel Construction Fee Per Vessel [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party \| €	€ 490,000	€ 390,000
Brave [Member] \| Capitalized Construction Supervision Fees [Member]
Related Party Transaction [Line Items]
Related party transaction, expenses from transactions with related party				$ 0	$ 1,790,789	$ 535,864