Consolidated Statements of Operations (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Gas sales, related party amounts	$ 80rgp_RelatedPartyTransactionGasSales	$ 71rgp_RelatedPartyTransactionGasSales	$ 42rgp_RelatedPartyTransactionGasSales
NGL sales, related party amounts	282rgp_RelatedPartyTransactionNglSales	81rgp_RelatedPartyTransactionNglSales	28rgp_RelatedPartyTransactionNglSales
Gathering, transportation and other fees, related party amounts	23	26	29
Cost of sales, related party amounts	$ 66us-gaap_CostsAndExpensesRelatedParty	$ 56us-gaap_CostsAndExpensesRelatedParty	$ 35us-gaap_CostsAndExpensesRelatedParty

This amount represents related party amount for natural gas midstream revenue. Midstream refers to those gas industry activities that fall between exploration and production (upstream) and refining and marketing (downstream). It may be applied to the gathering, processing, transmission and storage of natural gas; including the treating of natural gas to remove impurities, along with the sale of by-products such as residue gas, natural gas liquids and condensate.

No definition available.

+ Details

Name:	rgp_RelatedPartyTransactionGasSales
Namespace Prefix:	rgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This amount represents related party revenue related to midstream and downstream gas activities which may include the following: gathering from wells, processing to remove impurities, storage, transmission, and the sale of natural gas and related products.

+ References

No definition available.

+ Details

Name:	rgp_RelatedPartyTransactionGatheringTransportationAndOtherFees
Namespace Prefix:	rgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This amount represents related party revenue from the sales of natural gas liquids during the reporting period. Natural gas liquids are found with natural gas and usually are composed of ethane, propane, natural gasoline, butane, and isobutane.

+ References

No definition available.

+ Details

Name:	rgp_RelatedPartyTransactionNglSales
Namespace Prefix:	rgp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Costs of sales and operating expenses for the period incurred from transactions with related parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

Name:	us-gaap_CostsAndExpensesRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration