Consolidated Balance Sheets (Parentheticals) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Accounts receivable, reserve	$ 1,818,482	$ 2,357,191
Accumulated depreciation, vessels	218,669,885	177,771,755
Accumulated amortization, other fixed assets	$ 1,402,584	$ 1,137,562
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	25,000,000	25,000,000
Preferred stock, issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	700,000,000	700,000,000
Common stock, issued (in shares)	12,917,027	11,661,797
Common stock, outstanding (in shares)	12,917,027	11,661,797