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Derivative Financial Instruments - Summary of Non-designated Hedges (Detail) - Derivatives not designated as hedging instruments € in Thousands, £ in Thousands, SFr in Thousands	Sep. 30, 2025 GBP (£) derivative_instrument	Sep. 30, 2025 EUR (€) derivative_instrument	Sep. 30, 2025 CHF (SFr) derivative_instrument	Dec. 31, 2024 GBP (£) derivative_instrument
Buy GBP / Sell USD Forward
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of instruments	4	4	4	3
Notional amount | £	£ 109,300			£ 54,400
Buy USD / Sell GBP Forward
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of instruments	4	4	4	3
Notional amount | £	£ 109,300			£ 54,400
Buy EUR / Sell USD Forward
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of instruments	2	2	2
Notional amount | €		€ 35,900
Buy USD / Sell EUR Forward
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of instruments	2	2	2
Notional amount | €		€ 35,900
Buy CHF / Sell USD Forward
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of instruments	1	1	1
Notional amount | SFr			SFr 6,700
Buy USD / Sell CHF Forward
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of instruments	1	1	1
Notional amount | SFr			SFr 6,700

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- Definition

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Nominal or face amount used to calculate payment on derivative.

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