Condensed Consolidated Statements of Operations and Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Statement [Abstract]
Net earnings from discontinued operations, tax expense	$ 2.5		$ 7.2
(loss) from disposal of discontinued businesses, tax (benefit)	$ (5.0)	$ (1.4)	$ (4.9)

Amount of tax expense (benefit) on gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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