Income taxes - Components of Net Deferred Tax Asset (Liability) (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Tax effect of temporary differences related to:
Net noncurrent deferred tax asset (liability)	$ 42.6	$ 40.5
Tax effect of temporary differences related to:
Net noncurrent deferred tax asset (liability)	$ (64.1)	$ (63.5)

Amount of deferred tax liability attributable to taxable temporary differences.

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