Derivative Instruments and Hedging Transactions - Summary of Aggregate Gross and Net Derivative Receivables and Payables Balances (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Jun. 30, 2026
Nettable derivative assets:
Gross derivative receivable	$ 310,368	$ 333,173
Amounts Netted	(19,032)	(15,197)
Cash Collateral Pledge	0	0
Net Derivative	291,336	317,976
Nettable derivative liabilities:
Gross derivative payable	49,526	66,242
Amounts Netted	(1,362)	(2,490)
Cash Collateral Pledge	(24,309)	(23,834)
Net derivative payables	23,855	39,918
Open sale and purchase commitments
Nettable derivative assets:
Gross derivative receivable	224,802	316,650
Amounts Netted	(19,032)	(15,197)
Cash Collateral Pledge	0	0
Net Derivative	205,770	301,453
Nettable derivative liabilities:
Gross derivative payable	4,654	4,056
Amounts Netted	(1,362)	(2,490)
Cash Collateral Pledge	0	0
Net derivative payables	3,292	1,566
Liability on margin accounts
Nettable derivative liabilities:
Gross derivative payable	31,068	30,480
Amounts Netted	0	0
Cash Collateral Pledge	(24,309)	(23,834)
Net derivative payables	6,759	6,646
Futures contracts
Nettable derivative assets:
Gross derivative receivable	61,132	8,683
Amounts Netted	0	0
Cash Collateral Pledge	0	0
Net Derivative	61,132	8,683
Nettable derivative liabilities:
Gross derivative payable	425	2,543
Amounts Netted	0	0
Cash Collateral Pledge	0	0
Net derivative payables	425	2,543
Forward contracts
Nettable derivative assets:
Gross derivative receivable	24,434	7,840
Amounts Netted	0	0
Cash Collateral Pledge	0	0
Net Derivative	24,434	7,840
Nettable derivative liabilities:
Gross derivative payable	13,379	29,163
Amounts Netted	0	0
Cash Collateral Pledge	0	0
Net derivative payables	$ 13,379	$ 29,163

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