Acquisition of Gordon Trucking, Inc. Allocation of Purchase Price (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014
Business Acquisition [Line Items]
Cash Acquired from Acquisition	$ (20,000,000)
Cash paid (before netting $20 million cash acquired)	115,900,000
Stock Issued During Period, Shares, Acquisitions	2,860,000
Earn Out Agreement	13,600,000	13,600,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Gordon Trucking Company, Inc [Member]
Business Acquisition [Line Items]
Cash paid (before netting $20 million cash acquired)	130,900,000
Value of common stock issued (2.86 million shares)	41,100,000
Total fair value of consideration transferred (before netting $20 million cash acquired), excluding debt assumed	172,000,000
Historical book value of GTI assets and liabilities	92,125,000
Property, Plant, and Equipment	(17,912,000)
Other assets	3,450,000
Liabilities	(18,576,000)
Fair value of tangible net assets acquired	59,087,000
Identifiable intangibles at acquisition-date fair value	19,042,000
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	$ 93,871,000