Discontinued Operations and Assets and Liabilities Held for Sale - Summary of Discontinued Operations (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]
Total revenues	$ 24.6	$ 94.7
Pretax loss	(17.1)	(4.1)
Income tax expense	(4.2)	(1.0)
Loss from discontinued operations, net of income tax benefit	$ (12.9)	$ (3.1)

Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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+ Details

- Definition

Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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