Schedule II - Consolidated Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance For Doubtful Accounts And Sales Allowances
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 14,489	$ 12,404	$ 13,694
Additions charged to costs and expenses	4,262	1,791	1,536
Deductions	(5,919)	(2,794)	(4,128)
Other	(144)	3,088	1,302
Balance at end of year	12,688	14,489	12,404
Inventory Valuation Reserve
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	37,233	34,040	38,879
Additions charged to costs and expenses	5,291	10,071	8,616
Deductions	(6,331)	(6,540)	(9,049)
Other	1,917	(338)	(4,406)
Balance at end of year	$ 38,110	$ 37,233	$ 34,040

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

No definition available.

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

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- Definition

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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