The percentage of ownership in the investee accounted for under the cost method of accounting.

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- Definition

Period for creating allowance for doubtful accounts.

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No definition available.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 35
-Section 50
-Paragraph 1
-Subparagraph (b)
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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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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- Definition

Original amount of cost-method investments at the acquisition date.

+ References

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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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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Note 1 - Description of Business and Summary of Significant Accounting Policies (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2019	Jun. 30, 2018
Advertising Expense	$ 1,200,000	$ 1,600,000	$ 1,500,000
Period for Creating Allowance for Doubtful Accounts	120 days
Provision for Doubtful Accounts	$ 2,200,000	2,400,000	1,900,000
Asset Retirement Obligation, Ending Balance	1,000,000	1,100,000
Asset Retirement Obligation, Accretion Expense	$ 54,000	$ 71,000	$ 15,000
Accounting Standards Update 2016-02 [Member] \| Subsequent Event [Member]
Operating Lease, Right-of-Use Asset				$ 19,900,000
Operating Lease, Liability, Total				$ 19,900,000
Sales Revenue, Services, Net [Member] \| Customer Concentration Risk [Member] \| Automotive [Member]
Concentration Risk, Percentage	25.00%	25.00%	22.00%
Tarzian [Member] \| Common Stock [Member]
Cost Method Investments, Ownership Percentage					32.40%
Tarzian [Member] \| Dividends Liquidation Dissolution [Member]
Cost Method Investments, Ownership Percentage					67.90%
Syncbak [Member]
Cost Method Investments, Original Cost			$ 3,000,000