Recent Accounting Pronouncements - Operating Lease Assets and Liabilities (Details) - USD ($)	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 22,845,697		$ 7,540,871
Current portion of operating lease liabilities	21,094,309		7,615,371
Lease liabilities - long term	$ 1,744,619		686,422
Discount rate	5.48%
Minimum
Lessee, Lease, Description [Line Items]
Discount rate		1.33%
Maximum
Lessee, Lease, Description [Line Items]
Discount rate		6.08%
Weighted Average
Lessee, Lease, Description [Line Items]
Discount rate		1.67%
Chartered-in contracts greater than 12 months
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 20,712,287		6,207,253
Current portion of operating lease liabilities	20,451,549		6,974,943
Lease liabilities - long term	$ 253,970		0
Discount rate	5.37%
Office leases
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 2,133,410		1,333,618
Current portion of operating lease liabilities	642,760		640,428
Lease liabilities - long term	$ 1,490,649		$ 686,422
Discount rate	5.80%