Restructuring Charges (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring and Related Activities [Abstract]
Restructuring costs			$ 12,800
Restructuring Reserve [Roll Forward]
Accrual, beginning balance			1,008
Restructuring costs	$ 0	$ (29)	233	$ 137
Utilization			(825)
Accrual, ending balance	$ 416		$ 416

No definition available.

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- Definition

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

Amount, after cash payment, 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 45
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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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- Definition

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

+ References

No definition available.

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- Definition

Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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