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Income Taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Segment Reporting Information [Line Items]
Effective tax rate	25.90%	22.40%
U.S. federal corporate tax rate	21.00%
Unrecognized tax benefits	$ 1,700,000
Impact of unrecognized tax benefits on tax liability	$ 1,400,000
United Kingdom
Segment Reporting Information [Line Items]
U.S. federal corporate tax rate	19.00%

X

- Definition

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

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unrecognized tax benefits.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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