Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets
Allowance for doubtful accounts and discounts	$ 2,010	$ 1,600
Stockholders' equity
Preferred stock, no par value
Preferred stock, shares authorized	2,500	2,500
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, no par value
Common stock, shares authorized	40,000	40,000
Common stock, shares issued	17,274	17,274
Common stock, shares outstanding	16,008	16,154

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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