Document and Entity Information Document	9 Months Ended
Document and Entity Information Document	Sep. 30, 2014
Entity Information [Line Items]
Document Type	8-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2014
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	Q3
Entity Registrant Name	QEP RESOURCES, INC.
Entity Central Index Key	0001108827
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer

Pro Forma Condensed Consolidated Statements of Operations Statement (USD $) In Millions, except Per Share data, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Scenario, Previously Reported [Member]
REVENUES
Gas sales	$ 609.2	$ 779.0	$ 667.4	$ 1,239.1
Oil sales	1,041.0	916.6	532.6	324.2
NGL Sales	179.3	294.1	322.1	309.8
Other revenue	5.1	189.0	181.6	200.8
Purchased gas, oil and NGL sales	780.1	757.1	646.1	1,085.3
Total Revenues	2,614.7	2,935.8	2,349.8	3,159.2
OPERATING EXPENSES
Purchased gas, oil and NGL expense	775.5	765.9	655.6	1,077.1
Lease operating expense	177.0	177.8	172.3	145.2
Gas, oil and NGL transportation and other handling costs	198.5	141.4	148.9	102.2
Gathering and other expense	4.8	90.6	88.0	107.3
General and administrative	147.0	191.1	266.6	123.2
Production and property taxes	160.8	166.5	103.4	105.4
Depreciation, depletion and amortization	712.5	1,016.0	905.3	765.6
Exploration expenses	4.7	11.9	11.2	10.5
Impairment	3.6	93.0	133.0	218.2
Total Operating Expenses	2,184.4	2,654.2	2,484.3	2,654.7
Net gain (loss) on property sales	(210.3)	103.0	1.2	1.4
OPERATING INCOME	220.0	384.6	(133.3)	505.9
Realized and unrealized gains (losses) on derivative contracts	(13.2)	58.9	441.9
Interest and other income	7.8	5.2	6.6	4.1
Income from unconsolidated affiliates	0.2	5.8	6.8	5.5
Loss from early extinguishment of debt			(0.6)	(0.7)
Interest expense	(128.4)	(163.3)	(122.9)	(90.0)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	86.4	291.2	198.5	424.8
Income tax provision	(26.1)	(119.8)	(66.5)	(154.4)
NET INCOME	60.3	171.4	132.0	270.4
Net income attributable to noncontrolling interest	0	(12.0)	(3.7)	(3.2)
NET INCOME ATTRIBUTABLE TO QEP	60.3	159.4	128.3	267.2
Weighted average common shares outstanding
Weighted Average Number of Shares Outstanding, Basic	180.0	179.2	177.8	176.5
Weighted Average Number of Shares Outstanding, Diluted	180.4	179.5	178.7	178.4
Dividends per common share (in dollars per share)	$ 0.06	$ 0.08	$ 0.08	$ 0.08
Scenario, Adjustment [Member]
REVENUES
Gas sales	0	0	0	0
Oil sales	0	0	0	0
NGL Sales	0	(101.9)	(137.9)	(180.1)
Other revenue	0	(166.6)	(154.1)	(177.9)
Purchased gas, oil and NGL sales	0	17.8	13.9	33.8
Total Revenues	0	(250.7)	(278.1)	(324.2)
OPERATING EXPENSES
Purchased gas, oil and NGL expense	0	17.6	15.1	33.8
Lease operating expense	0	3.5	3.4	3.0
Gas, oil and NGL transportation and other handling costs	0	80.6	49.2	55.6
Gathering and other expense	0	(82.2)	(79.8)	(98.7)
General and administrative	0	(30.7)	(18.2)	(25.6)
Production and property taxes	0	(5.2)	(4.9)	(4.9)
Depreciation, depletion and amortization	0	(52.2)	(55.1)	(48.7)
Exploration expenses	0	0	0	0
Impairment	0	0	0	0
Total Operating Expenses	0	(68.6)	(90.3)	(85.5)
Net gain (loss) on property sales	0	0.5	0	0
OPERATING INCOME	0	(181.6)	(187.8)	(238.7)
Realized and unrealized gains (losses) on derivative contracts	2.1	(1.4)	(8.4)
Realized and unrealized gains (losses) on derivative contracts proforma adjustments			7.4
Interest and other income	0	10.1	8.4	5.1
Income from unconsolidated affiliates	0	(5.8)	(6.8)	(5.5)
Loss from early extinguishment of debt			0	0
Interest expense		(1.7)	(3.4)	(2.1)
Interest expense proforma adjustments	19.1	19.7	9.2	11.0
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	21.2	(160.7)	(181.4)	(230.2)
Income tax provision	(8.1)	52.7	62.4	84.7
NET INCOME	13.1	(108.0)	(119.0)	(145.5)
Net income attributable to noncontrolling interest	0	12.0	3.7	3.2
NET INCOME ATTRIBUTABLE TO QEP	13.1	(96.0)	(115.3)	(142.3)
Pro Forma [Member]
REVENUES
Gas sales	609.2	779.0	667.4	1,239.1
Oil sales	1,041.0	916.6	532.6	324.2
NGL Sales	179.3	192.2	184.2	129.7
Other revenue	5.1	22.4	27.5	22.9
Purchased gas, oil and NGL sales	780.1	774.9	660.0	1,119.1
Total Revenues	2,614.7	2,685.1	2,071.7	2,835.0
OPERATING EXPENSES
Purchased gas, oil and NGL expense	775.5	783.5	670.7	1,110.9
Lease operating expense	177.0	181.3	175.7	148.2
Gas, oil and NGL transportation and other handling costs	198.5	222.0	198.1	157.8
Gathering and other expense	4.8	8.4	8.2	8.6
General and administrative	147.0	160.4	248.4	97.6
Production and property taxes	160.8	161.3	98.5	100.5
Depreciation, depletion and amortization	712.5	963.8	850.2	716.9
Exploration expenses	4.7	11.9	11.2	10.5
Impairment	3.6	93.0	133.0	218.2
Total Operating Expenses	2,184.4	2,585.6	2,394.0	2,569.2
Net gain (loss) on property sales	(210.3)	103.5	1.2	1.4
OPERATING INCOME	220.0	203.0	(321.1)	267.2
Realized and unrealized gains (losses) on derivative contracts	(11.1)	57.5	440.9
Interest and other income	7.8	15.3	15.0	9.2
Income from unconsolidated affiliates	0.2	0	0	0
Loss from early extinguishment of debt			(0.6)	(0.7)
Interest expense	(109.3)	(145.3)	(117.1)	(81.1)
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	107.6	130.5	17.1	194.6
Income tax provision	(34.2)	(67.1)	(4.1)	(69.7)
NET INCOME	73.4	63.4	13.0	124.9
Net income attributable to noncontrolling interest	0	0	0	0
NET INCOME ATTRIBUTABLE TO QEP	$ 73.4	$ 63.4	$ 13.0	$ 124.9
Weighted average common shares outstanding
Weighted Average Number of Shares Outstanding, Basic	180.0	179.2	177.8	176.5
Weighted Average Number of Shares Outstanding, Diluted	180.4	179.5	178.7	178.4
Dividends per common share (in dollars per share)	$ 0.06	$ 0.08	$ 0.08	$ 0.08
Continuing Operations [Member] \| Scenario, Previously Reported [Member]
Earnings Per Common Share Attributable to QEP
Earnings Per Share, Basic	$ 0.34	$ 0.89	$ 0.72	$ 1.51
Earnings Per Share, Diluted	$ 0.34	$ 0.89	$ 0.72	$ 1.50
Continuing Operations [Member] \| Pro Forma [Member]
Earnings Per Common Share Attributable to QEP
Earnings Per Share, Basic	$ 0.41	$ 0.35	$ 0.07	$ 0.71
Earnings Per Share, Diluted	$ 0.41	$ 0.35	$ 0.07	$ 0.70

Pro Forma Condensed Consolidated Balance Sheets Statement (USD $) In Millions, unless otherwise specified	Sep. 30, 2014
Scenario, Previously Reported [Member]
Assets, Current [Abstract]
Cash and cash equivalents	$ 0
Accounts receivable, net	599.4
Fair value of derivative contracts	32.6
Gas, oil and NGL inventories, at lower of average cost or market	16.4
Prepaid expenses and other	50.8
Current assets of discontinued operations held for sale	138.3
Total current assets	837.5
Property, Plant and Equipment (successful efforts method for oil and gas properties)
Proved properties	11,723.0
Unproved properties	1,120.5
Midstream	197.5
Marketing and resources	95.2
Material and supplies	55.3
Total Property, Plant and Equipment	13,191.5
Less Accumulated Depreciation, Depletion and Amortization
Exploration and production	4,915.0
Midstream	34.3
Marketing and resources	29.8
Total Accumulated Depreciation, Depletion and Amortization	4,979.1
Net Property, Plant and Equipment	8,212.4
Fair value of derivative contracts	12.7
Other noncurrent assets	39.4
Noncurrent assets of discontinued operations held for sale	1,174.2
TOTAL ASSETS	10,276.2
Liabilities, Current [Abstract]
Checks outstanding in excess of cash balances	36.8
Accounts payable and accrued expenses	691.4
Production and property taxes	73.5
Interest payable	34.1
Fair value of derivative contracts	4.5
Deferred income taxes	2.9
Current liabilities of discontinued operations	161.6
Total current liabilities	1,004.8
Long-term debt	3,115.5
Deferred income taxes	1,500.8
Asset retirement obligations	162.3
Fair value of derivative contracts	0.2
Other long-term liabilities	90.3
Noncurrent liabilities of discontinued operations held for sale	402.0
Common Shareholders' Equity	3,505.6
Noncontrolling interest	494.7
Total Equity	4,000.3
TOTAL LIABILITIES AND EQUITY	10,276.2
Scenario, Adjustment [Member]
Assets, Current [Abstract]
Cash and cash equivalents	2,500.0
Debt refinanced	230.0
Cash proceeds designated for debt repayment	(897.5)
Cash proceeds designated for transaction expenses	(35.0)
Accounts receivable, net	0
Fair value of derivative contracts	0
Gas, oil and NGL inventories, at lower of average cost or market	0
Prepaid expenses and other	0
Current assets of discontinued operations held for sale	(138.3)
Total current assets	1,199.2
Property, Plant and Equipment (successful efforts method for oil and gas properties)
Proved properties	0
Unproved properties	0
Midstream	0
Marketing and resources	0
Material and supplies	0
Total Property, Plant and Equipment	0
Less Accumulated Depreciation, Depletion and Amortization
Exploration and production	0
Midstream	0
Marketing and resources	0
Total Accumulated Depreciation, Depletion and Amortization	0
Net Property, Plant and Equipment	0
Fair value of derivative contracts	(3.5)
Other noncurrent assets	0
Noncurrent assets of discontinued operations held for sale	(1,174.2)
TOTAL ASSETS	21.5
Liabilities, Current [Abstract]
Checks outstanding in excess of cash balances	0
Accounts payable and accrued expenses	0
Production and property taxes	0
Interest payable	0
Fair value of derivative contracts	(4.3)
Deferred income taxes	0
Current liabilities of discontinued operations	(161.6)
Total current liabilities	(165.9)
Long-term debt	(897.5)
Deferred income taxes	0
Asset retirement obligations	0
Fair value of derivative contracts	0
Other long-term liabilities	0
Noncurrent liabilities of discontinued operations held for sale	(172.0)
Debt refinanced	(230.0)
Common Shareholders' Equity	1,981.6
Noncontrolling interest	(494.7)
Total Equity	1,486.9
TOTAL LIABILITIES AND EQUITY	21.5
Pro Forma [Member]
Assets, Current [Abstract]
Cash and cash equivalents	1,337.5
Accounts receivable, net	599.4
Fair value of derivative contracts	32.6
Gas, oil and NGL inventories, at lower of average cost or market	16.4
Prepaid expenses and other	50.8
Current assets of discontinued operations held for sale	0
Total current assets	2,036.7
Property, Plant and Equipment (successful efforts method for oil and gas properties)
Proved properties	11,723.0
Unproved properties	1,120.5
Midstream	197.5
Marketing and resources	95.2
Material and supplies	55.3
Total Property, Plant and Equipment	13,191.5
Less Accumulated Depreciation, Depletion and Amortization
Exploration and production	4,915.0
Midstream	34.3
Marketing and resources	29.8
Total Accumulated Depreciation, Depletion and Amortization	4,979.1
Net Property, Plant and Equipment	8,212.4
Fair value of derivative contracts	9.2
Other noncurrent assets	39.4
Noncurrent assets of discontinued operations held for sale	0
TOTAL ASSETS	10,297.7
Liabilities, Current [Abstract]
Checks outstanding in excess of cash balances	36.8
Accounts payable and accrued expenses	691.4
Production and property taxes	73.5
Interest payable	34.1
Fair value of derivative contracts	0.2
Deferred income taxes	2.9
Current liabilities of discontinued operations	0
Total current liabilities	838.9
Long-term debt	2,218.0
Deferred income taxes	1,500.8
Asset retirement obligations	162.3
Fair value of derivative contracts	0.2
Other long-term liabilities	90.3
Noncurrent liabilities of discontinued operations held for sale	0
Common Shareholders' Equity	5,487.2
Noncontrolling interest	0
Total Equity	5,487.2
TOTAL LIABILITIES AND EQUITY	$ 10,297.7

Pro Forma Adjustments (Notes)	9 Months Ended
Pro Forma Adjustments (Notes)	Sep. 30, 2014
Pro Forma Adjustments [Abstract]
Pro Forma Adjustments [Text Block]	Pro Forma Adjustments (a) To record proceeds of $2.5 billion from the disposition, net of $230.0 million to refinance indebtedness at QEP Midstream, QEP debt extinguishment of $897.5 million, which includes $297.5 million related to QEP's revolving credit facility and $600.0 million related to QEP's term loan, and estimated related fees and expenses of $35.0 million. (b) To eliminate assets and liabilities of discontinued operations related to the sale of QEP Field Services. (c) To adjust shareholders' equity which is primarily related to the gain on sale of QEP Field Services that would have been recorded as of September 30, 2014. (d) To eliminate noncontrolling interest of discontinued operations related to the sale of QEP Field Services. (e) To eliminate interest expense, assets and liabilities and realized and unrealized gain or loss associated with interest rate derivatives, including the tax impact, related to certain QEP indebtedness that was extinguished in conjunction with the disposition. (f) To eliminate revenues and expenses and the associated intercompany elimination adjustments, including the tax impact, related to the operations of QEP Field Services, excluding QEP's Haynesville Gathering System. (g) With the exception of the disposition related adjustments specifically discussed in note (e) above, no additional pro forma adjustments were required for the nine months ended September 30, 2014, since the results of operations for QEP Field Services, excluding QEP's Haynesville Gathering System, were presented as discontinued operations in the Company's third quarter 2014 Form 10-Q.