Condensed Consolidated Statements of Earnings and Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Statement [Abstract]
Net earnings (loss) from discontinued operations, tax (benefit) expense	$ (0.5)	$ 2.2	$ 1.2	$ 8.7
Gain (Loss) from disposal of discontinued business, tax (benefit)	$ (4.6)	$ (5.9)	$ (4.9)	$ (5.4)

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

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