Average fixed interest rate related to the group of interest rate derivatives.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Derivative Instruments - Narrative (Details) £ in Millions, $ in Millions	Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Apr. 30, 2025 USD ($)	Apr. 30, 2025 GBP (£)	Nov. 04, 2024 USD ($)	Aug. 12, 2024	Aug. 05, 2024 USD ($)	May 31, 2024 USD ($)
Derivatives not designated as hedging instruments:
Derivative [Line Items]
Derivative, notional amount			$ 375
Interest rate swaps
Derivative [Line Items]
Derivative, notional amount					$ 400		$ 500
Derivative, average fixed interest rate						4.30%
Interest rate swaps \| Receive Fixed/Pay Variable
Derivative [Line Items]
Derivative, notional amount	$ 650	$ 650
Interest rate swaps \| Receive Variable/Pay Fixed
Derivative [Line Items]
Derivative, notional amount		400
Forward exchange contracts
Derivative [Line Items]
Derivative, notional amount	700	600
Cross currency swaps
Derivative [Line Items]
Derivative, notional amount	3,000	$ 3,000						$ 500
Derivative, Fair Value, Net	$ 500
Cross currency swaps \| Derivatives not designated as hedging instruments:
Derivative [Line Items]
Derivative, notional amount			925	£ 700
Cross currency swaps \| Not Designated as Hedging Instrument, Economic Hedge
Derivative [Line Items]
Derivative, notional amount			$ 700
Cross currency swaps \| United States of America, Dollars
Derivative [Line Items]
Derivative, average fixed interest rate								5.45%
Cross currency swaps \| Switzerland, Francs
Derivative [Line Items]
Derivative, average fixed interest rate								2.218%