Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Name:	us-gaap_RestrictedCashAndCashEquivalentsNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Cash, cash equivalents, and Restricted cash (Details)	Jun. 30, 2021 USD ($) vessel	Mar. 31, 2021 USD ($) vessel	Dec. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jul. 29, 2019 vessel
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 79,278,151		$ 69,927,594		$ 98,532,141	$ 53,583,898
Restricted cash - current	4,446,177		18,846,177		0	5,471,470
Restricted cash - noncurrent	75,000		75,000		74,917	74,917
Total cash, cash equivalents and restricted cash shown in the condensed consolidated statements of cash flows	$ 83,799,328	$ 83,799,328	$ 88,848,771	$ 98,607,058	$ 98,607,058	$ 59,130,285
Number of vessels acquired \| vessel							6
Ultramax Vessels
Cash and Cash Equivalents [Line Items]
Number of vessels acquired \| vessel	2	2