Business Segments (Details)	12 Months Ended
	Dec. 31, 2014 Segment Platform Fractionator mi
Segment Reporting Information [Line Items]
Number of reportable segments	5
Number of miles of pipelines	51,300
Number of fractionators	22
Number of offshore hub platforms	6
NGL Pipelines and Services [Member]
Segment Reporting Information [Line Items]
Number of miles of pipelines	19,300
Number of fractionators	15
Onshore Natural Gas Pipelines and Services [Member]
Segment Reporting Information [Line Items]
Number of miles of pipelines	19,300
Onshore Crude Oil Pipelines and Services [Member]
Segment Reporting Information [Line Items]
Number of miles of pipelines	5,400
Number of tractor-trailors	560
Offshore Pipelines And Services [Member]
Segment Reporting Information [Line Items]
Number of miles of pipelines	2,350
Number of offshore hub platforms	6
Petrochemical and Refined Products Services [Member] | Propylene Operations [Member]
Segment Reporting Information [Line Items]
Number of miles of pipelines	680
Petrochemical and Refined Products Services [Member] | Refined Products Operations [Member]
Segment Reporting Information [Line Items]
Number of miles of pipelines	4,200