Long-Term Debt (Details)				1 Months Ended	12 Months Ended
	Jan. 21, 2014 USD ($) item	Nov. 17, 2013 USD ($) item	Sep. 24, 2013 USD ($) item	Mar. 31, 2015 USD ($) item	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($) item	Mar. 31, 2017 USD ($)	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)
Long-Term Debt
Financing costs paid					$ 99,785	$ 13,990,720	$ 11,220,812
Drawdowns						676,819,873	80,086,143
Presented as follows:
Total debt obligations									$ 770,102,728	$ 836,368,372
Less: deferred financing fees				$ 13,296,216	23,748,116	13,296,216	13,296,216		20,138,480	23,748,116	$ 13,296,216
Current portion of long-term debt									65,978,785	66,265,643
Long-term debt—net of current portion and deferred financing fees									683,985,463	746,354,613
Total									$ 749,964,248	812,620,256
Long-term Debt, Other Disclosures [Abstract]
Deferred finance fees, beginning					23,748,116	13,296,216
Additions					99,785	12,951,085
Amortization					(3,709,421)	(2,499,185)	(830,899)
Deferred finance fees, end				$ 13,296,216	$ 20,138,480	$ 23,748,116	$ 13,296,216
Royal Bank of Scotland plc (RBS)
Long-Term Debt
Original loan amount								$ 135,224,500
Number of tranches in which loan facility is divided | item								3
Period after non-compliance prepayment required to be made					1 month
Minimum market adjusted security cover ratio as percentage of aggregate outstanding loan balance in the event of lender release									175.00%
Margin in the event of lender release (as a percent)									2.75%
Presented as follows:
Total debt obligations									$ 99,882,500	109,494,500
Royal Bank of Scotland plc (RBS) | Prior to September 26, 2014 | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)					1.50%
Royal Bank of Scotland plc (RBS) | From September 26, 2014 through September 25, 2015 | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)					2.00%
Royal Bank of Scotland plc (RBS) | After September 26, 2015 | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)					2.50%
Tranche A
Long-Term Debt
Original loan amount			$ 47,600,000
Number of semi annual installments | item			12
Semi-annual installment			$ 1,700,000
Balloon payment			$ 27,200,000
Presented as follows:
Total debt obligations									34,000,000	37,400,000
Tranche B
Long-Term Debt
Original loan amount		$ 34,500,000
Number of semi annual installments | item		11
Semi-annual installment		$ 1,278,500
Balloon payment		$ 20,456,000
Presented as follows:
Total debt obligations									25,570,000	28,127,000
Tranche C
Long-Term Debt
Original loan amount	$ 53,100,000
Number of semi annual installments | item	14
Semi-annual installment	$ 1,827,500
Balloon payment	$ 27,520,000
Presented as follows:
Total debt obligations									40,312,500	43,967,500
2015 Debt Facility
Long-Term Debt
Original loan amount											758,000,000
Number of tranches in which loan facility is divided | item				4
Number of VLGC newbuildings secured by loan | item				18
Loan-to-contract cost ratio before fees (as a percent)				55.00%
Commitment fee (as a percent)				40.00%
Presented as follows:
Total debt obligations									$ 670,220,228	726,873,872
2015 Debt Facility | LIBOR
Long-Term Debt
Interest Rate									0.98%
Commercial Financing
Long-Term Debt
Original loan amount											$ 249,000,000
Term				7 years
Interest Rate									3.73%
Presented as follows:
Total debt obligations									$ 227,512,277	241,442,384
Commercial Financing | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)				2.75%
Commercial Financing | 50% or more but less than 75% vessels financed are employed under time charters | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)				2.50%
Commercial Financing | 75% or more vessels financed are employed under time charters | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)				2.25%
Commercial Financing | Minimum | 50% or more but less than 75% vessels financed are employed under time charters
Long-Term Debt
Percent of vessels financed that are employed under time charters											50.00%
Commercial Financing | Minimum | 75% or more vessels financed are employed under time charters
Long-Term Debt
Percent of vessels financed that are employed under time charters											75.00%
Commercial Financing | Maximum | 50% or more but less than 75% vessels financed are employed under time charters
Long-Term Debt
Percent of vessels financed that are employed under time charters											75.00%
KEXIM Direct Financing
Long-Term Debt
Original loan amount											$ 204,000,000
Term				12 years
Interest Rate									3.43%
Presented as follows:
Total debt obligations									$ 177,680,534	194,827,596
KEXIM Direct Financing | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)				2.45%
KEXIM Guaranteed and K-sure Insured
Long-Term Debt
Original loan amount											305,000,000
KEXIM Guaranteed
Long-Term Debt
Original loan amount											202,000,000
Term				12 years
Interest Rate									2.38%
Presented as follows:
Total debt obligations									$ 175,773,718	192,736,763
KEXIM Guaranteed | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)				1.40%
K-sure Insured
Long-Term Debt
Original loan amount											$ 103,000,000
Term				12 years
Interest Rate									2.48%
Presented as follows:
Total debt obligations									$ 89,253,699	$ 97,867,129
K-sure Insured | LIBOR
Long-Term Debt
Margin added to LIBOR for interest rate on loan facility (as a percent)				1.50%