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Significant Accounting Policies (Details)					3 Months Ended		12 Months Ended
Significant Accounting Policies (Details)	Feb. 10, 2026	Dec. 27, 2024	Oct. 30, 2020	Aug. 03, 2020	Sep. 30, 2026 USD ($) investment	Sep. 30, 2025	Jun. 30, 2026 USD ($) investment	Jun. 30, 2025	Oct. 30, 2025	Sep. 30, 2021	May 27, 2021
Temporary Equity [Line Items]
Qualifying assets					80.52%		81.94%
Number of asset going through foreclosure \| investment					0		0
Total assets at fair value are in non-accrual status					0.20%		0.70%
Excise tax expense					$ 0
Registration expenses					$ 0		$ 0
Time dividends have remained unpaid					2 years		2 years
5.50% Preferred Stock
Temporary Equity [Line Items]
Dividend rate				5.50%	5.50%	5.50%
Dividend rate	5.50%		5.50%		5.50%	5.50%	5.50%	5.50%
6.50% Preferred Stock
Temporary Equity [Line Items]
Dividend rate				6.50%	6.50%	6.50%
Dividend rate					6.50%	6.50%	6.50%	6.50%
Series A
Temporary Equity [Line Items]
Dividend rate					5.35%
7.50% Preferred Stock
Temporary Equity [Line Items]
Dividend rate		7.50%		7.50%	7.50%
Dividend rate					7.50%		7.50%
3.364% 2026 Notes
Temporary Equity [Line Items]
Stated rate					3.364%
3.364% 2026 Notes \| Convertible Notes
Temporary Equity [Line Items]
Stated rate					3.364%
3.364% 2026 Notes \| Unsecured Debt
Temporary Equity [Line Items]
Stated rate					3.364%		3.364%				3.364%
3.437% 2028 Notes
Temporary Equity [Line Items]
Stated rate					3.437%
3.437% 2028 Notes \| Unsecured Debt
Temporary Equity [Line Items]
Stated rate					3.437%		3.437%			3.437%
5.50% 2030 Notes
Temporary Equity [Line Items]
Stated rate					5.50%				5.50%
5.50% 2030 Notes \| Unsecured Debt
Temporary Equity [Line Items]
Stated rate					5.50%		5.50%		5.50%