Income Taxes (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Income Taxes [Abstract]
Federal tax rate	21.00%		35.00%
Provisional tax expense			$ 13.0
Net deferred tax assets			8.3
One-time mandatory repatriation tax			$ 4.7
Effective tax rate	32.70%	26.00%

Tax Cuts And Jobs Act Of 2017, Change In Tax Rate, Income Tax Expense (Benefit)

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Tax Cuts And Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)

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Tax Cuts And Jobs Act of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense (Benefit)

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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 changes in the income tax rates.

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