Forward Currency Contracts - Open Forward Foreign Currency Contract (Details) € in Thousands, £ in Thousands, $ in Thousands, $ in Thousands	Sep. 30, 2022 GBP (£)	Sep. 30, 2022 USD ($)	Sep. 30, 2022 EUR (€)	Sep. 30, 2022 CAD ($)	Sep. 30, 2021 GBP (£)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 EUR (€)	Sep. 30, 2021 CAD ($)
Open Forward Foreign Currency Contract [Line Items]
Unrealized appreciation on forward currency contracts		$ 32,333				$ 2,716
Unrealized depreciation on forward currency contracts		0				(2,626)
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 07/17/2023
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | £	£ 10,058
Currency to be purchased		12,706
Unrealized appreciation on forward currency contracts		1,459
Unrealized depreciation on forward currency contracts		0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 10/30/2023
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold				$ 18,425				$ 18,425
Currency to be purchased		13,783				13,783
Unrealized appreciation on forward currency contracts		372				0
Unrealized depreciation on forward currency contracts		0				(660)
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 2/27/2025
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | €			€ 26,000				€ 26,000
Currency to be purchased		31,803				31,803
Unrealized appreciation on forward currency contracts		4,637				426
Unrealized depreciation on forward currency contracts		0				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 2/28/2023
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | £	8,925				£ 8,925
Currency to be purchased		11,219				11,219
Unrealized appreciation on forward currency contracts		1,226				0
Unrealized depreciation on forward currency contracts		0				(769)
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 3/27/2023
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | £	3,780				3,780
Currency to be purchased		4,804				4,804
Unrealized appreciation on forward currency contracts		572				0
Unrealized depreciation on forward currency contracts		0				(272)
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 3/31/2025
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | £	13,945				13,945
Currency to be purchased		19,149				19,149
Unrealized appreciation on forward currency contracts		3,538				335
Unrealized depreciation on forward currency contracts		0				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 4/28/2023 Contract 1
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold	2,228						6,760
Currency to be purchased		2,903				8,044
Unrealized appreciation on forward currency contracts		408				40
Unrealized depreciation on forward currency contracts		0				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 4/28/2023 Contract 2
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold			13,960		2,228
Currency to be purchased		16,735				2,903
Unrealized appreciation on forward currency contracts		2,778				0
Unrealized depreciation on forward currency contracts		0				(88)
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 4/28/2023 Contract 3
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | €			6,760				13,960
Currency to be purchased		8,044				16,735
Unrealized appreciation on forward currency contracts		1,287				343
Unrealized depreciation on forward currency contracts		0				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 4/29/2022
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | €							€ 9,300
Currency to be purchased						10,861
Unrealized appreciation on forward currency contracts						106
Unrealized depreciation on forward currency contracts						0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 7/17/2023
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | £					10,058
Currency to be purchased						12,706
Unrealized appreciation on forward currency contracts						0
Unrealized depreciation on forward currency contracts						(796)
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 7/18/2025
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold				7,000
Currency to be purchased		5,386
Unrealized appreciation on forward currency contracts		236
Unrealized depreciation on forward currency contracts		0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 7/21/2025
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | €			€ 10,100
Currency to be purchased		10,918
Unrealized appreciation on forward currency contracts		448
Unrealized depreciation on forward currency contracts		0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 8/27/2024 Contract 1
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold				25,000	25,000
Currency to be purchased		19,609				34,298
Unrealized appreciation on forward currency contracts		1,267				663
Unrealized depreciation on forward currency contracts		0				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 8/27/2024 Contract 2
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold				30,000				30,000
Currency to be purchased		23,399				23,399
Unrealized appreciation on forward currency contracts		1,399				0
Unrealized depreciation on forward currency contracts		0				(41)
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 8/27/2024 Contract 3
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold	25,000							25,000
Currency to be purchased		34,298				19,609
Unrealized appreciation on forward currency contracts		6,285				75
Unrealized depreciation on forward currency contracts		0				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 8/30/2024
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold				$ 22,600				$ 22,600
Currency to be purchased		17,739				17,739
Unrealized appreciation on forward currency contracts		1,156				81
Unrealized depreciation on forward currency contracts		0				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Macquarie Bank Limited, Settlement Date 9/03/2024
Open Forward Foreign Currency Contract [Line Items]
Currency to be sold | £	£ 20,550				£ 20,550
Currency to be purchased		28,297				28,297
Unrealized appreciation on forward currency contracts		5,265				647
Unrealized depreciation on forward currency contracts		$ 0				$ 0