Business Combinations, Divestitures and Discontinued Operations - Summary of Discontinued Operations (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2022
Discontinued Operations and Disposal Groups [Abstract]
Total revenues	$ 111.7	$ 206.4
Pretax earnings from operations	20.5	16.4
Pretax loss on divestiture	(1.0)	(1.0)
Pretax earnings	19.5	15.4
Income tax expense	6.2	5.2
Earnings from discontinued operations, net of income tax expense	$ 13.3	$ 10.2

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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