Accounts Receivable (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Reserves for sales discounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Reserves for sales discounts on products shipped under promotional programs	$ 19,785	$ 15,652

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.

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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant