Restructuring (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Restructuring and Related Activities [Abstract]
Restructuring expense	$ 2,642	$ 0
Accrued restructuring costs, accrued liabilities	11,700
Accrued restructuring costs, other liabilities (long-term)	$ 5,400

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.

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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration