Description of Business and Basis of Presentation - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended	3 Months Ended	6 Months Ended			6 Months Ended				0 Months Ended		6 Months Ended				0 Months Ended	6 Months Ended		0 Months Ended
	Apr. 02, 2013	Jun. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Aug. 02, 2013	Jun. 30, 2014 GIP I Entities and GIP II	Jun. 30, 2014 Aggregate	Mar. 31, 2014 MidCon Compression, L.L.C. hp	Mar. 31, 2014 MidCon Compression, L.L.C. Minimum Compression	Apr. 02, 2013 Common Units	Jun. 30, 2014 Common Units GIP I Entities and GIP II	Jun. 30, 2014 Common Units Williams Acquisition	Jun. 30, 2014 Common Units Publicly Owned	Jun. 30, 2014 Class B Units GIP I Entities and GIP II	Jun. 30, 2014 Class B Units Williams Acquisition	Apr. 02, 2013 Underwriters Overallotment Option	Jun. 30, 2014 General Partner	Jun. 30, 2014 General Partner GIP I Entities and GIP II	Jul. 01, 2014 General Partner Williams Acquisition Subsequent Event
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items]
Units outstanding						2,068,692					48,742,361	40,137,695	101,171,762	6,340,022	6,340,022		2,068,692
General partnership interest	2.00%	2.00%	2.00%			50.00%						50.00%					1.00%	1.00%	100.00%
Limited partnership interest						26.60%	22.50%						48.90%
Consideration paid for acquisition								$ 160
Number of compression units acquired									100
Combined capacity of compression units								200,000
Market value of common units					300
Common stock, shares issued		772,819	909,219							10,350,000						1,350,000
Net offering proceeds	399.8	44.6	52.2
Payments for commissions		0.4	0.5
Capital contribution from Partnerships' general partner	$ 8.4	$ 1.0	$ 1.0	$ 0.9
Common stock, par value	$ 39.86