Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Effective tax rate [Abstract]
Effective income tax rate	24.60%	18.80%	24.30%	34.40%
Reversal of tax accruals		$ 3.6
Adjusted effective income tax rate		36.20%
Statutory Federal income tax rate			21.00%		35.00%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations, excluding the effect of reversal of certain account accruals due to change in accounting estimate.

No definition available.

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- References

No definition available.

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- Definition

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

+ References

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

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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