Credit Facilities	3 Months Ended
Mar. 31, 2017
Debt Disclosure [Abstract]
Credit Facilities	Note F: Credit Facilities In May 2014, the Company entered into a credit agreement and related documents with Alliance Bank providing for a revolving line of credit for the Company. The credit agreement and related documents with Alliance Bank (collectively, the "Alliance Credit Agreement") provides up to a $5.0 million revolving line of credit. Amounts due under the Alliance Credit Agreement bear interest at a fixed annual rate of 3.95%. Any advances are secured by the Company's inventories, accounts receivable, cash, marketable securities, and equipment. We are subject to certain covenants under the Alliance Credit Agreement. In April 2016, we entered into an agreement with Alliance Bank amending the Alliance Credit Agreement to extend the maturity date from April 1, 2016 to May 12, 2017. At March 31, 2017, we had no borrowings under the Alliance Credit Agreement, and we were in compliance with all financial covenants. As of March 31, 2017, available borrowings were $1.7 million, and we do not anticipate renewing the line of credit

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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