Business Combinations, Divestitures, Discontinued Operations and Assets and Liabilities Held for Sale - Summary of Discontinued Operations (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Discontinued Operations and Disposal Groups [Abstract]
Total revenues	$ 308.6	$ 79.2
Pretax earnings from operations	16.2	6.6
Pretax loss on divestiture	(0.7)	(6.0)
Pretax earnings	15.5	0.6
Income tax expense	5.0	0.1
Earnings from discontinued operations, net of income tax expense	$ 10.5	$ 0.5

Amount before tax of income (loss) from a discontinued operation. 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.

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.

+ References

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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.

+ References + Details