Derivatives - Schedule of Interest Rate Swap Derivative Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Sep. 30, 2024
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited
Open Forward Foreign Currency Contract [Line Items]
Unrealized Appreciation	$ 972
Unrealized Depreciation	0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Maturing June 15, 2029 1
Open Forward Foreign Currency Contract [Line Items]
Notional Amount	150,000
Unrealized Appreciation	972
Unrealized Depreciation	0
Open Forward Foreign Currency Contract, Identifier [Axis]: SMBC Capital Markets, Inc.
Open Forward Foreign Currency Contract [Line Items]
Unrealized Appreciation	9,289	$ 31,486
Unrealized Depreciation	0	0
Open Forward Foreign Currency Contract, Identifier [Axis]: SMBC Capital Markets, Inc., Maturing June 15, 2029
Open Forward Foreign Currency Contract [Line Items]
Notional Amount		600,000
Unrealized Appreciation		9,263
Unrealized Depreciation		0
Open Forward Foreign Currency Contract, Identifier [Axis]: SMBC Capital Markets, Inc., Maturing June 15, 2029 1
Open Forward Foreign Currency Contract [Line Items]
Notional Amount	600,000
Unrealized Appreciation	1,988
Unrealized Depreciation	0
Open Forward Foreign Currency Contract, Identifier [Axis]: SMBC Capital Markets, Inc., Maturing November 5, 2028 1
Open Forward Foreign Currency Contract [Line Items]
Notional Amount	225,000	225,000
Unrealized Appreciation	1,779	8,925
Unrealized Depreciation	0	0
Open Forward Foreign Currency Contract, Identifier [Axis]: SMBC Capital Markets, Inc., Maturing November 5, 2028 2
Open Forward Foreign Currency Contract [Line Items]
Notional Amount	225,000	225,000
Unrealized Appreciation	5,522	13,298
Unrealized Depreciation	$ 0	$ 0