Organization and Summary of Significant Accounting Policies - Additional Information 1 (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Significant financial instruments with off-balance sheet risk	$ 0
Long-term debt	0	$ 1,200,000
Line-of-credit outstanding balance	0	0
Interest and penalties recognized in consolidated statements of income	0
Accrued interest or penalties related to uncertain tax positions	0	0
Reserve for reduction in account receivable	1,184,000	1,070,000
Trade promotions to customers	$ 3,335,000	$ 3,410,000
Minimum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	3 years
Useful lives of intangible assets	5 years
Maximum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	20 years
Useful lives of intangible assets	15 years
Production Equipment \| Minimum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	15 years
Production Equipment \| Maximum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	20 years
Production Support Equipment \| Minimum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	3 years
Production Support Equipment \| Maximum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	10 years
Office Furniture and Equipment \| Minimum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	10 years
Office Furniture and Equipment \| Maximum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	20 years
Office Equipment \| Minimum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	3 years
Office Equipment \| Maximum
Schedule Of Organization And Presentation Of Financial Statements [Line Items]
Useful life of property, plant and equipment	5 years

Schedule of organization and presentation of financial statements.

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Trade promotions and incentives.

+ References

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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- Definition

The fair value of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 10
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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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