U.K. Pension Plan Amount Recognized in Balance Sheet (Details) - Pension Plan [Member] - Foreign Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Accrued expenses	$ 14,945	$ 13,879
Other long-term liabilities	39,983	86,404
Defined benefit plan, liabilities recognized in balance sheet	$ 54,928	$ 100,283

Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current.

+ References

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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