Goodwill and Other Intangibles - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Other Intangible Assets
Intangible Asset, Acquired, Finite-Lived [Line Items]
Other intangible assets	$ 59.6	$ 58.1
Amortization of intangible assets	6.1	9.2
Computer Software
Intangible Asset, Acquired, Finite-Lived [Line Items]
Other intangible assets	2,352.0	2,155.1
Amortization of intangible assets	$ 672.3	$ 597.6	$ 509.4