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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Long-term Debt (Details) - USD ($)	3 Months Ended
Long-term Debt (Details) - USD ($)	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Mar. 31, 2019	Mar. 31, 2015
Debt obligations
Total debt obligations			$ 694,104,514	$ 710,096,616
Less: deferred financing fees	$ 14,005,830		13,261,559	14,005,830
Total			680,842,955	696,090,786
Presented as follows:
Current portion of long-term debt			63,968,414	63,968,414
Long-term debt—net of current portion and deferred financing fees			616,874,541	632,122,372
Total			680,842,955	696,090,786
Deferred financing fees
Deferred finance fees, beginning	14,005,830
Amortization	(744,271)	$ (793,212)
Deferred finance fees, end	$ 13,261,559
Japanese Financings
Debt obligations
Total debt obligations			209,992,612	213,476,121
Corsair Japanese Financing
Debt obligations
Total debt obligations			46,583,333	47,395,833
Concorde Japanese Financing
Debt obligations
Total debt obligations			51,153,846	51,961,538
Corvette Japanese Financing
Debt obligations
Total debt obligations			51,692,308	52,500,000
CJNP Japanese Financing
Debt obligations
Total debt obligations			20,144,375	20,506,250
CMNL Japanese Financing
Debt obligations
Total debt obligations			19,103,720	19,446,131
CNML Japanese Financing
Debt obligations
Total debt obligations			21,315,030	21,666,369
2015 Debt Facility
Long-Term Debt
Original loan amount					$ 758,000,000
Debt obligations
Total debt obligations			484,111,902	496,620,495
Commercial Financing
Debt obligations
Total debt obligations			172,612,210	175,687,613
KEXIM Direct Financing
Debt obligations
Total debt obligations			122,074,140	125,860,144
KEXIM Guaranteed
Debt obligations
Total debt obligations			126,621,194	130,366,568
K-sure Insured
Debt obligations
Total debt obligations			$ 62,804,358	$ 64,706,170