Condensed Consolidated Statements of Operations and Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Net (loss) from discontinued operations, tax expense	$ 4.8		$ 4.7
(Loss) from disposal of discontinued businesses, tax expense	$ 0.1	$ (1.4)	$ 0.1

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

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