Long-term Debt - Captain Markos Dual-Fuel Japanese Financing (Details) - Captain Markos Dual-Fuel Japanese Financing - USD ($) $ in Thousands	Mar. 31, 2023	Jun. 30, 2023
Long-term Debt
Other capitalized expenditures	$ 25,000
Value of vessel transferred	$ 56,000
Description of variable rate basis	one-month SOFR plus a credit adjustment spread of 0.1148% (reflecting the difference between unsecured LIBOR and secured SOFR) and a margin of 2.475%
Credit adjustment spread	0.1148%
Margin added to base interest rate under debt facility	2.475%
Monthly brokerage commission (as a percent)	1.25%
Loan term period	13 years
Brokerage commission fee on delivery purchase option (as a percent)	1.00%
Balloon payment	$ 19,400
Fixed interest rate		6.39%
Straight-line principal through February 29, 2028
Long-term Debt
Monthly principal payments on debt	210
Straight-line principal starting March 31, 2028
Long-term Debt
Monthly principal payments on debt	$ 250

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