Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowance for doubtful accounts (in Dollars)	$ 201	$ 183
Preferred stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,000,000us-gaap_PreferredStockSharesAuthorized	2,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Common Class A [Member]
Common Stock, Par Value (in Dollars per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized	60,000,000	60,000,000
Common Stock, Shares Issued	25,475,662	25,285,029
Common Stock, Shares Outstanding	20,894,286	20,768,784
Treasury stock, Shares	4,581,376	4,516,245
Common Class B [Member]
Common Stock, Par Value (in Dollars per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized	80,000,000	80,000,000
Common Stock, Shares Issued	4,251,889	4,220,117
Common Stock, Shares Outstanding	3,494,865	3,467,410
Treasury stock, Shares	757,024	752,707

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.

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