Financial Instruments and Fair Value Disclosures (Swaps) (Details) - USD ($)	Mar. 31, 2022	Mar. 31, 2021
Interest rate swaps
Derivative Instruments
Nominal value	$ 235,000,000	$ 366,254,131
1.091% interest rate swap due on March 2025 \| Citibank N.A.
Derivative Instruments
Fixed interest rate (as a percent)	1.091%
Nominal value	$ 188,000,000	200,000,000
Final settlement amount	$ 95,200,000
1.145% interest rate swap due on March 2025 \| ING Bank N. V. Member
Derivative Instruments
Fixed interest rate (as a percent)	1.145%
Nominal value	$ 47,000,000	$ 50,000,000
Final settlement amount	$ 23,800,000
1.468% interest rate swap due on March 2022 \| ABN
Derivative Instruments
Fixed interest rate (as a percent)		1.468%
Nominal value		$ 26,325,000
1.380% interest rate swap due on March 2022 \| Citibank N.A.
Derivative Instruments
Fixed interest rate (as a percent)		1.38%
Nominal value		$ 39,487,500
1.213% interest rate swap due March 2022 \| Citibank N.A.
Derivative Instruments
Fixed interest rate (as a percent)		1.213%
Nominal value		$ 35,750,774
1.161% interest rate swap due March 2022 \| Citibank N.A.
Derivative Instruments
Fixed interest rate (as a percent)		1.161%
Nominal value		$ 14,690,857

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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