Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Preferred stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	1,000,000us-gaap_PreferredStockSharesAuthorized	1,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value (in Dollars per share)	$ 0.01	$ 0.01
Common Class A [Member]
Common stock, shares authorized	60,000,000	60,000,000
Common stock, shares outstanding	30,157,533	29,889,332
Common Class B [Member]
Common stock, shares authorized	20,000,000	20,000,000
Common stock, shares outstanding	10,092,981	9,999,122
Treasury stock, shares	2,616,657	2,560,580

Face amount or stated value per share of common stock.

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