Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Common Class A [Member]
Par value (in dollars per share)	$ 0.01	$ 0.01
Shares authorized (in shares)	20,000,000	20,000,000
Shares issued (in shares)	15,922,879	15,746,609
Shares outstanding (in shares)	15,706,507	15,746,609
Common Class B [Member]
Par value (in dollars per share)	$ 0.01	$ 0.01
Shares authorized (in shares)	5,000,000	5,000,000
Shares issued (in shares)	2,350,000	2,350,000
Shares outstanding (in shares)	2,350,000	2,350,000
Accounts receivable allowance	$ 1,613	$ 1,767
Drivers' advances and other receivables, allowance	$ 1,009	$ 1,290
Treasury stock, shares (in shares)	216,372