Amount Of Mdth Per Day Reserved Transportation Capacity - Off-Peak Months

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- Definition

Amount Of Mdth Per Day Reserved Transportation Capacity - Peak Months

+ References

No definition available.

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- Definition

The amount of operating income received by subsidiary from operations as outlined by the agreement.

+ References

No definition available.

+ Details

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- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ 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 210.5-03.1(e))

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Related Parties

-URI http://asc.fasb.org/extlink&oid=16382449

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.6-07.1(c))

-URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 07

-Paragraph b

-Subparagraph 1

-Article 6

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Related-Party Transaction (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Related Party Transaction [Line Items]
Oil and NGL income sharing (in millions)	$ 0str_OilIncomeSharingAmountsPerAgreement	$ 0.6str_OilIncomeSharingAmountsPerAgreement	$ 2.5str_OilIncomeSharingAmountsPerAgreement
Questar Gas [Member] \| Sales [Member] \| Questar Pipeline [Member]
Related Party Transaction [Line Items]
Related Party Revenue	73.3	76.3	74.0
Questar Gas [Member] \| General and Administrative Expense [Member] \| Questar Pipeline [Member]
Related Party Transaction [Line Items]
Related Party Expense	3.8	3.5	8.8
Questar Corp [Member] \| General and Administrative Expense [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Related Party Expense	47.8	48.4	49.3
Questar Corp [Member] \| General and Administrative Expense [Member] \| Questar Pipeline [Member]
Related Party Transaction [Line Items]
Related Party Expense	25.8	28.2	24.5
Questar Corp [Member] \| Interest Expense [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Related Party Expense	0.1	0.5	0.6
Questar Corp [Member] \| Interest Income [Member] \| Questar Pipeline [Member]
Related Party Transaction [Line Items]
Related Party Revenue	0.1	0.2	0.1
Affiliated Entity [Member] \| Rent Expense [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Related Party Expense			0.4
Affiliated Entity [Member] \| Rent Expense [Member] \| Questar Pipeline [Member]
Related Party Transaction [Line Items]
Related Party Expense			0.3
Questar And Other Affiliates [Member] \| General and Administrative Expense [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Related Party Expense	6.1	6.7	13.6
Questar And Other Affiliates [Member] \| General and Administrative Expense [Member] \| Questar Pipeline [Member]
Related Party Transaction [Line Items]
Related Party Expense	5.0	4.9
Questar Pipeline [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Amount of Mdth per day reserved transportation capacity on Questar Pipeline - peak months	916
Amount of Mdth per day reserved transportation capacity on Questar Pipeline - off-peak months	841
Questar Pipeline [Member] \| General and Administrative Expense [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Related Party Expense	3.7	3.7
Questar Pipeline [Member] \| Cost of Sales [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Related Party Expense	72.9	73.0	73.6
Wexpro [Member] \| Sales [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Oil and NGL income sharing (in millions)	0	0.6	2.5
Wexpro [Member] \| Cost of Sales [Member] \| Questar Gas [Member]
Related Party Transaction [Line Items]
Related Party Expense	$ 349.7	$ 294.6	$ 274.0