The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

Name:	us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Acquisitions (Details Textual) $ in Thousands		12 Months Ended
Acquisitions (Details Textual) $ in Thousands	Jun. 24, 2014 USD ($) truck trailer	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Business Acquisition [Line Items]
Payments to acquire businesses		$ 0	$ 0	$ 44,508
Crude Transportation [Member] \| Chesapeake crude oil trucking assets [Member]
Business Acquisition [Line Items]
Payments to acquire businesses	$ 44,000
Trucks purchased \| truck	124
Trailers purchased \| trailer	122