Gas and Liquids Stored Underground and Gas and NGLs Receivables and Payables (Policies)	9 Months Ended
Sep. 30, 2018
Gas Balancing Arrangements [Abstract]
Gas and Liquids Stored Underground and Gas and NGLs Receivables and Payables, Policy	The operating subsidiaries of the Partnership provide storage services whereby they store natural gas or NGLs on behalf of customers and also periodically hold customer gas under PAL services. Since the customers retain title to the gas held by the Partnership in providing these services, the Partnership does not record the related gas on its balance sheet.

Disclosure of accounting policy for gas balancing arrangements.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 815
-Section 55
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6475423&loc=d3e69394-109492

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 815
-Section 55
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6475423&loc=d3e69409-109492

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Period Type:	duration