Acquisitions Pro Forma Financial Results (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Combinations [Abstract]
Pro forma net sales	$ 205,683	$ 183,424	$ 626,414	$ 568,270
Pro forma income (loss) from continuing operations	(11,830)	(8,436)	(31,909)	(52,840)
Pro forma net income (loss)	$ (11,830)	$ 121,005	$ (31,909)	$ 87,355
Basic income (loss) per share (in dollars per share)	$ (0.41)	$ (0.31)	$ (1.15)	$ (1.93)
Diluted income (loss) per share (in dollars per share)	$ (0.41)	$ (0.31)	$ (1.15)	$ (1.93)
Transaction costs not considered ongoing		$ 0		$ 15,000

Business Combination, Costs Expensed Not Considered Ongoing

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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- References

No definition available.

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