Financial Instruments and Fair Value Disclosures (Carrying and FV) (Details) - USD ($)	Sep. 30, 2019	Mar. 31, 2019
Fair value
Carrying Value	$ 665,545,499	$ 696,090,786
Corsair Japanese Financing
Fair value
Carrying Value	45,770,833	47,395,833
Corsair Japanese Financing | Level 2
Fair value
Fair Value	48,310,731	45,901,900
Concorde Japanese Financing
Fair value
Carrying Value	50,346,154	51,961,538
Concorde Japanese Financing | Level 2
Fair value
Fair Value	53,385,688	50,176,288
Corvette Japanese Financing
Fair value
Carrying Value	50,884,615	52,500,000
Corvette Japanese Financing | Level 2
Fair value
Fair Value	53,988,368	50,671,689
CJNP Japanese Financing
Fair value
Carrying Value	19,782,500	20,506,250
CJNP Japanese Financing | Level 2
Fair value
Fair Value	21,231,215	20,918,881
CMNL Japanese Financing
Fair value
Carrying Value	18,761,310	19,446,131
CMNL Japanese Financing | Level 2
Fair value
Fair Value	20,352,955	19,862,056
CNML Japanese Financing
Fair value
Carrying Value	20,963,690	21,666,369
CNML Japanese Financing | Level 2
Fair value
Fair Value	$ 22,778,604	$ 22,137,090