Income Taxes - U.S. Tax Reform Legislation (Details)	3 Months Ended
Mar. 31, 2018 USD ($)
Income Tax Disclosure [Line Items]
Tax impact of global intangible low-taxed income ("GILTI") provisions of U.S. tax reform

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.

No definition available.

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