Recent Accounting Pronouncements (Schedule of ASU 2017-07 Adoption) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Item Effected [Line Items]
Cost of sales	$ 61,904	$ 113,428	$ 145,473	$ 243,158
Selling, general and administrative expenses	8,385	5,922	16,381	12,952
Restructuring and impairment charges	0	369	0	1,726
Other income (expense)	$ 588	184	$ 969	(115)
As Reported [Member]
Item Effected [Line Items]
Cost of sales		113,344		242,990
Selling, general and administrative expenses		5,903		12,914
Restructuring and impairment charges		369		2,146
Other income (expense)		81		99
Reclassifications [Member]
Item Effected [Line Items]
Cost of sales		84		168
Selling, general and administrative expenses		19		38
Restructuring and impairment charges				(420)
Other income (expense)		$ 103		$ (214)

The aggregate cost of goods produced and sold and services rendered during the reporting period.

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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)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311

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