Derivative Instruments - Schedule of Foreign Currency Forward Contracts and Interest Rate Swap (Details) € in Thousands, £ in Thousands, $ in Thousands	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Mar. 31, 2024 GBP (£)	Sep. 30, 2023 USD ($)	Sep. 30, 2023 EUR (€)	Sep. 30, 2023 GBP (£)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative assets at fair value	$ 0			$ 4,910
Derivative liability at fair value	35,005			47,519
Foreign currency forward contract
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative assets at fair value	0			4,910
Derivative liability at fair value	670			0
Interest rate swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative assets at fair value	0			0
Derivative liability at fair value	34,335			47,519
Open Forward Foreign Currency Contract, Identifier [Axis]: EUR Foreign Currency Forward Contract, Maturing May 9, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount to be Purchased	28,312
Notional Amount to be Sold | €		€ 26,350
Derivative assets at fair value	0
Derivative liability at fair value	188
Open Forward Foreign Currency Contract, Identifier [Axis]: EUR Foreign Currency Forward Contract, Maturing November 9, 2023
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount to be Purchased				42,182
Notional Amount to be Sold | €					€ 38,026
Derivative assets at fair value				1,857
Derivative liability at fair value				0
Open Forward Foreign Currency Contract, Identifier [Axis]: GBP Foreign Currency Forward Contract, Maturing May 9, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount to be Purchased	32,738
Notional Amount to be Sold | £			£ 26,292
Derivative assets at fair value	0
Derivative liability at fair value	482
Open Forward Foreign Currency Contract, Identifier [Axis]: GBP Foreign Currency Forward Contract, Maturing November 9, 2023
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount to be Purchased				72,098
Notional Amount to be Sold | £						£ 56,556
Derivative assets at fair value				3,053
Derivative liability at fair value				0
Open Forward Foreign Currency Contract, Identifier [Axis]: Interest rate swap, Maturing February 15, 2029
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	300,000			300,000
Derivative assets at fair value	0			0
Derivative liability at fair value	1,824			7,000
Open Forward Foreign Currency Contract, Identifier [Axis]: Interest rate swap, Maturing January 15, 2027
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	350,000			350,000
Derivative assets at fair value	0			0
Derivative liability at fair value	$ 32,511			$ 40,519