Commitments and Contingencies - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2018
Commitments and Contingencies Disclosure [Line Items]
Contract receivable, due in next twelve months	$ 91,040,878		$ 91,040,878
Contract receivable, due in year two	22,782,759		22,782,759
Contract receivable, due in year three	10,970,170		10,970,170
Contract receivable, due in year four	$ 3,519,740		$ 3,519,740
Astrid and Kazak [Member]
Commitments and Contingencies Disclosure [Line Items]
Sale leaseback transaction, rent expense	12 months	12 months	12 months
Astrid and Kazak [Member] \| Time Charters [Member]
Commitments and Contingencies Disclosure [Line Items]
Minimum lease payments, sale leaseback transactions, next twelve months	$ 4,703,679		$ 4,703,679
Astrid and Kazak [Member] \| Time Charters [Member] \| Charter Hire Expenses [Member]
Commitments and Contingencies Disclosure [Line Items]
Sale leaseback transaction, term of lease			$ 2,906,617

Commitments and contingencies disclosure.

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- Definition

Sale leaseback transaction term of lease.

+ References

No definition available.

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- Definition

Amount billed to customers under long-term contracts or programs to be collected in the second fiscal year following the latest fiscal year. Excludes amounts due that have been withheld because of retainage provisions in a contract. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 910
-SubTopic 310
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=68065756&loc=d3e49354-109356

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- Definition

Amount billed to customers under long-term contracts or programs to be collected in the next fiscal year following the latest fiscal year. Excludes amounts due that have been withheld because of retainage provisions in a contract. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount billed to customers under long-term contracts or programs to be collected in the fourth fiscal year following the latest fiscal year. Excludes amounts due that have been withheld because of retainage provisions in a contract. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount billed to customers under long-term contracts or programs to be collected in the third fiscal year following the latest fiscal year. Excludes amounts due that have been withheld because of retainage provisions in a contract. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77914019&loc=d3e50824-112756

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- Definition

The amount of the current period expense recorded for use of the property in connection with the transaction involving the sale of property to another party and the lease of the property back to the seller.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77902758&loc=d3e41499-112717

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