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Derivatives and Hedging Activity - Designated and Non-Designated Hedges (Details) € in Thousands, £ in Thousands, SFr in Thousands, $ in Thousands, $ in Thousands	Mar. 31, 2025 EUR (€) contract	Mar. 31, 2025 GBP (£) contract	Mar. 31, 2025 AUD ($) contract	Mar. 31, 2025 CHF (SFr) contract	Mar. 31, 2025 USD ($) contract
Derivatives
Number of Contracts	512	512	512	512	512
Foreign exchange contracts \| Long \| EUR
Derivatives
Number of Contracts	26	26	26	26	26
Aggregate Notional Amount \| €	€ 466,138
Foreign exchange contracts \| Long \| GBP
Derivatives
Number of Contracts	11	11	11	11	11
Aggregate Notional Amount \| £		£ 99,442
Foreign exchange contracts \| Long \| AUD
Derivatives
Number of Contracts	2	2	2	2	2
Aggregate Notional Amount \| $			$ 742,152
Foreign exchange contracts \| Short \| EUR
Derivatives
Number of Contracts	145	145	145	145	145
Aggregate Notional Amount \| €	€ 780,589
Foreign exchange contracts \| Short \| GBP
Derivatives
Number of Contracts	169	169	169	169	169
Aggregate Notional Amount \| £		£ 622,555
Foreign exchange contracts \| Short \| AUD
Derivatives
Number of Contracts	74	74	74	74	74
Aggregate Notional Amount \| $			$ 1,381,072
Foreign exchange contracts \| Short \| CHF
Derivatives
Number of Contracts	31	31	31	31	31
Aggregate Notional Amount \| SFr				SFr 18,597
Interest rate swaps – Paying fixed rates \| USD
Derivatives
Number of Contracts	36	36	36	36	36
Aggregate Notional Amount \| $					$ 3,132,242
Interest rate swaps – Receiving fixed rates \| USD
Derivatives
Number of Contracts	5	5	5	5	5
Aggregate Notional Amount \| $					$ 2,038,380
Interest rate futures \| USD
Derivatives
Number of Contracts	7	7	7	7	7
Aggregate Notional Amount \| $					$ 54,800
Interest rate caps \| USD
Derivatives
Number of Contracts	3	3	3	3	3
Aggregate Notional Amount \| $					$ 513,646
Credit instruments \| USD
Derivatives
Number of Contracts	2	2	2	2	2
Aggregate Notional Amount \| $					$ 45,000
Interest rate swap guarantees \| USD
Derivatives
Number of Contracts	1	1	1	1	1
Aggregate Notional Amount \| $					$ 88,496