Subsequent Event (Details) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Business Acquisition [Line Items]
Number of subordinated units	6,273,970
Compressor Systems, Inc. [Member]
Business Acquisition [Line Items]
Date of acquisition	Jul. 20, 2014
Effective date of acquisition	Aug. 04, 2014
Purchase price	$ 825.0