Restructuring (Activity in Restructuring Accruals) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Restructuring Reserve [Roll Forward]
Balance at January 1, 2019	$ 45,095
Adjustment for ASC 842	(42,248)		$ 42,200
Restructuring charges	2,832	$ 6,187
Payments	(1,026)
Balance at March 31, 2019	$ 4,653		$ 45,095

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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