Note 11 - Acquisitions (Details Textual) - USD ($) $ in Millions	1 Months Ended
Nov. 30, 2015	Jul. 31, 2015
Buckler Transport, Inc. [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		$ 13.7
FTL [Member]
Payments to Acquire Businesses, Gross	$ 5.4

The amount of property, plant, and equipment recognized as of the acquisition date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

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Balance Type:	debit
Period Type:	instant