Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Common Class A [Member]
Common Stock, Par Value (in dollars per share)		$ 0.01
Common Class B [Member]
Common Stock, Par Value (in dollars per share)		$ 0.01
Allowance for doubtful accounts	$ 222	$ 235
Property and equipment, accumulated depreciation and amortization	17,810	17,233
Leased property under capital leases, accumulated depreciation and amortization	$ 4,417	$ 4,310

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (SX 210.5-02.4)
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The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Face amount or stated value per share of common stock.

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