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Long-Term Debt (Condensed) (Details) - USD ($)	3 Months Ended
Long-Term Debt (Condensed) (Details) - USD ($)	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Mar. 31, 2016
Debt obligations
Total debt obligations			$ 820,711,318	$ 836,368,372
Less: deferred financing fees	$ 23,748,116		22,899,494	23,748,116
Total			797,811,824	812,620,256
Presented as follows:
Current portion of long-term debt			65,978,785	66,265,643
Long-term debt—net of current portion and deferred financing fees			731,833,039	746,354,613
Total			797,811,824	812,620,256
Deferred financing fees
Deferred finance fees, beginning	23,748,116
Additions	99,785
Amortization	(948,407)	$ (223,740)
Deferred finance fees, end	$ 22,899,494
Royal Bank of Scotland plc (RBS)
Debt obligations
Total debt obligations			108,216,000	109,494,500
Tranche A
Debt obligations
Total debt obligations			37,400,000	37,400,000
Tranche B
Debt obligations
Total debt obligations			26,848,500	28,127,000
Tranche C
Debt obligations
Total debt obligations			43,967,500	43,967,500
2015 Debt Facility
Debt obligations
Total debt obligations			712,495,318	726,873,872
Commercial Financing
Debt obligations
Total debt obligations			237,906,927	241,442,384
KEXIM Direct Financing
Debt obligations
Total debt obligations			190,475,726	194,827,596
KEXIM Guaranteed
Debt obligations
Total debt obligations			188,431,597	192,736,763
K-sure Insured
Debt obligations
Total debt obligations			$ 95,681,068	$ 97,867,129