Organization And Summary Of Significant Accounting Policies - Income Statement Impact (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition
Cost of sales	$ 180,280	$ 120,483	$ 491,339	$ 330,370	$ 463,054	$ 468,202
Research and development	518	1,329	1,528	3,083	3,456	2,534
Selling and administrative expenses	14,234	13,293	46,349	37,118	52,506	58,515
Other expense (income), net	$ 1,502	(404)	$ 2,533	4,322	(2,104)	(4,266)
Calculated under Revenue Guidance in Effect before Topic 606
Revenue, Initial Application Period Cumulative Effect Transition
Cost of sales		120,684		330,973	462,848	466,990
Research and development		1,338		3,110	2,951	2,399
Selling and administrative expenses		13,322		37,200	49,479	57,784
Other expense (income), net		(643)		3,610	1,634	(2,188)
Difference between Revenue Guidance in Effect before and after Topic 606 \| Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition
Cost of sales		(201)		(603)	206	1,212
Research and development		(9)		(27)	505	135
Selling and administrative expenses		(29)		(82)	3,027	731
Other expense (income), net		$ 239		$ 712	$ (3,738)	$ (2,078)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

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-Name Accounting Standards Codification
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No definition available.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
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-Publisher FASB
-Name Accounting Standards Codification
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-Section 30
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