Note 7 - Debt (Details) - Current and Long-term Debt (Parentheticals)	Jun. 30, 2013	Dec. 31, 2012
Revenue Equipment Installment Notes [Member]
Note 7 - Debt (Details) - Current and Long-term Debt (Parentheticals) [Line Items]
Interest rate on notes payable, current	4.70%	5.20%
Interest rate on notes payable, long-term	4.70%	5.20%
Real Estate Note [Member]
Note 7 - Debt (Details) - Current and Long-term Debt (Parentheticals) [Line Items]
Interest rate on notes payable, current	2.70%	2.70%
Interest rate on notes payable, long-term	2.70%	2.70%
Other Note Payable [Member]
Note 7 - Debt (Details) - Current and Long-term Debt (Parentheticals) [Line Items]
Interest rate on notes payable, current	2.30%	3.00%
Interest rate on notes payable, long-term	2.30%	3.00%