Derivative Instruments and Hedging Activities - Schedule of Amounts Recorded On Balance Sheet Related To Cumulative Basis Adjustments For Fair Value Hedges (Detail) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Carrying Amount of Hedged Liabilities [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Long-term debt	$ 881.4	$ 837.6
Cumulative Amount of Fair Value Hedging Adjustment Included in Carrying Amount of Hedged Liabilities [Member] | Long Term Debt Noncurrent [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Long-term debt	$ (115.0)	$ (158.6)