Note 2 - Prepaid Expenses and Other (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Tires In Service [Member]
Prepaid expenses	$ 5,064	$ 4,438
License Fees Member [Member]
Prepaid expenses	4,921	4,397
Parts And Tires Inventory [Member]
Prepaid expenses	4,011	3,754
Insurance premiums	1,730	1,537
Other	2,408	2,734
	$ 18,134	$ 16,860

Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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-Section 02
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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