Partners' Capital and Distributions (Details 4)	Sep. 30, 2012
PNG
Partners Capital and Distribution
Noncontrolling interests, ownership percentage of noncontrolling owners	36.00%
SLC Pipeline
Partners Capital and Distribution
Noncontrolling interests, ownership percentage of noncontrolling owners	25.00%

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

No definition available.

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant