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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Cost incurred during the reporting period in transporting goods and services to customers. Includes freight-out costs.

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Note 1 - Summary of Significant Interim Accounting Policies (Details Textual)		3 Months Ended								12 Months Ended
	Feb. 04, 2015	Dec. 31, 2015 USD ($) shares	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Five Largest [Member]
Concentration Risk, Percentage										25.70%	25.50%
Concentration Risk Number of Customers										5	5
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Concentration Risk, Percentage										0.00%	0.00%
Accounts Receivable, Net, Current		$ 7,702,000				$ 7,128,000				$ 7,702,000	$ 7,128,000
Customer Concentration Risk [Member] \| Sales Revenue, Net [Member] \| Five Largest [Member]
Concentration Risk, Percentage										23.30%	22.00%
Concentration Risk Number of Customers										5	5
Revenue, Net										$ 48,900,000	$ 43,153,000
Customer Concentration Risk [Member] \| Sales Revenue, Net [Member] \| Largest [Member]
Concentration Risk, Percentage										6.00%	5.70%
Revenue, Net										$ 12,537,000	$ 11,215,000
Customer Concentration Risk [Member] \| Largest [Member]
Other Receivables		$ 2,569,000				3,758,000				$ 2,569,000	$ 3,758,000
Supplier Concentration Risk [Member] \| Central America [Member]
Concentration Risk, Percentage										22.00%	22.00%
Maximum [Member] \| Building [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		5.00%								5.00%
Maximum [Member] \| Building Improvements [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		20.00%								20.00%
Maximum [Member] \| Machinery, Equipment and Fixtures [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		33.33%								33.33%
Maximum [Member] \| Transportation Equipment [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		33.33%								33.33%
Maximum [Member]
Cash and Cash Equivalents Term										3 years
Minimum [Member] \| Building [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		2.50%								2.50%
Minimum [Member] \| Building Improvements [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		2.50%								2.50%
Minimum [Member] \| Machinery, Equipment and Fixtures [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		10.00%								10.00%
Minimum [Member] \| Transportation Equipment [Member]
Property Plant and Equipment Depreciation Straight Line Percentage		20.00%								20.00%
Selling, General and Administrative Expenses [Member]
Shipping, Handling and Transportation Costs										$ 9,327,000	$ 9,170,000
HPI [Member] \| Trade Names [Member]
Indefinite-lived Intangible Assets (Excluding Goodwill), Fair Value Disclosure												$ 4,700,000
2013 Incentive Stock and Awards Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized \| shares		4,168,786								4,168,786
Stock Split from [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	2
Finite-Lived Intangible Assets, Amortization Expense, Year Five		$ 920,000								$ 920,000
Finite-lived Intangible Assets Amortization Expense Year Six		920,000								920,000
Finite Lived Intangible Assets Amortization Expense Year Seven		920,000								920,000
Advertising Expense										$ 135,000	114,000
Number of Reportable Segments										2
Amortization of Intangible Assets										$ 2,066,000	2,065,000
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months		2,042,000								2,042,000
Finite-Lived Intangible Assets, Amortization Expense, Year Two		1,920,000								1,920,000
Finite-Lived Intangible Assets, Amortization Expense, Year Three		1,420,000								1,420,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four		920,000								920,000
Finite Lived Intangible Assets Amortization Expense Year Eight		460,000								$ 460,000
Pension Plan Prior Service Costs Amortization Term										20 years
Accounts Receivable, Net, Current		29,914,000				27,956,000				$ 29,914,000	27,956,000
Revenue, Net		53,192,000	$ 56,662,000	$ 54,116,000	$ 46,347,000	49,701,000	$ 52,291,000	$ 53,230,000	$ 41,027,000
Other Receivables		$ 3,262,000				$ 4,135,000				$ 3,262,000	$ 4,135,000