Taxes on Income (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Effective income tax rate	1275.00%	7.40%	22.90%	(2.20%)
Change in tax rate, adjustment	$ (1.5)		$ (1.5)
Employee share-based payments, amount			$ 1.5
Employee share-based payments, percentage			39.30%
Operating loss carryforwards, valuation allowance	$ 14.9		$ 14.9

Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Deferred Tax Liability, Provisional Income Tax Benefit, Adjustment

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to equity-based compensation costs.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible equity-based compensation costs.

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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