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Long-term Debt (Details) - USD ($)	3 Months Ended
Long-term Debt (Details) - USD ($)	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Mar. 31, 2015
Debt obligations
Total debt obligations	$ 589,132,910		$ 602,087,981
Less: deferred financing fees	9,994,699		10,615,937
Total	579,138,211		591,472,044
Presented as follows:
Current portion of long-term debt	51,820,283		51,820,283
Long-term debt-net of current portion and deferred financing fees	527,317,928		539,651,761
Total	579,138,211		591,472,044
Deferred financing fees
Deferred finance fees, beginning	10,615,937
Additions	68,603
Amortization	(689,841)	$ (2,394,510)
Deferred finance fees, end	9,994,699
2015 Facility
Long-Term Debt
Original loan amount				$ 758,000,000
Debt obligations
Total debt obligations	376,032,750		385,011,186
Commercial Financing
Debt obligations
Total debt obligations	155,055,698		155,205,698
KEXIM Direct Financing
Debt obligations
Total debt obligations	85,931,225		89,474,512
KEXIM Guaranteed
Debt obligations
Total debt obligations	90,491,820		93,997,081
K-sure Insured
Debt obligations
Total debt obligations	44,554,007		46,333,895
Japanese Financings
Debt obligations
Total debt obligations	213,100,160		217,076,795
Corsair Japanese Financing
Debt obligations
Total debt obligations	40,083,333		40,895,833
Concorde Japanese Financing
Debt obligations
Total debt obligations	44,692,308		45,500,000
Corvette Japanese Financing
Debt obligations
Total debt obligations	45,230,769		46,038,462
CMNL Japanese Financing
Debt obligations
Total debt obligations	16,364,435		16,706,845
CNML Japanese Financing
Debt obligations
Total debt obligations	18,504,315		18,855,655
Cresques Japanese Financing
Debt obligations
Total debt obligations	$ 48,225,000		$ 49,080,000