Acquisition of Gordon Trucking, Inc. Acquisition pro forma information (Details) $ in Thousands	12 Months Ended
Dec. 31, 2013 USD ($)
Acquisition of Gordon Trucking, Inc. [Abstract]
Business Acquisition, Pro Forma Revenue	$ 961,525
Business Acquisition, Pro Forma Net Income (Loss)	$ 90,821

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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Balance Type:	credit
Period Type:	duration