Equity - Schedule of the Company's Equity Activity (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity [Abstract]
Balance			$ 149.4	$ 111.1
Net earnings	$ 48.0	$ 5.3	74.6	33.4
Other comprehensive income	0.8	2.5	(0.9)	5.6
Separation-related adjustments				0.2
Adoption of ASU 2014-09			0.9
Share-based compensation			7.2	5.2
Issuance of common stock				18.8
Issuance of share-based awards, net of withholdings and other			0.5	(0.7)
Balance	$ 231.7	$ 173.6	$ 231.7	$ 173.6

Separation related adjustments.

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Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of stock value of such awards forfeited. Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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