Derivative Contracts (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Forecasted production from proved reserves (in hundredths)	100.00%
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	$ 0	[1]	$ 20.1	[1]
Fair Value of Derivative Contracts, Gross [Abstract]
Derivative Asset, Fair Value, Gross	9.2				6.5
Derivative Liability, Fair Value, Gross	80.0				32.0
Commodity Contract [Member] | Short-term [Member]
Fair Value of Derivative Contracts, Gross [Abstract]
Derivative Asset, Fair Value, Gross					5.5
Derivative Liability, Fair Value, Gross	73.0				29.4
Commodity Contract [Member] | Long-term [Member]
Fair Value of Derivative Contracts, Gross [Abstract]
Derivative Asset, Fair Value, Gross					0.4
Derivative Liability, Fair Value, Gross	2.3				0
Interest Rate Swap [Member] | Short-term [Member]
Fair Value of Derivative Contracts, Gross [Abstract]
Derivative Asset, Fair Value, Gross	0				0
Derivative Liability, Fair Value, Gross	4.7				2.6
Interest Rate Swap [Member] | Long-term [Member]
Fair Value of Derivative Contracts, Gross [Abstract]
Derivative Asset, Fair Value, Gross					0.6
Derivative Liability, Fair Value, Gross	0				0
Interest Rate Swap [Member] | QEP Resources [Member]
Derivative Contracts - Volumes and Prices
Maturity	Mar. 31, 2017
Fixed Rate Paid (in hundredths)	0.96%
Swap [Member] | Natural Gas Sales (MMbtu) [Member] | 2014 [Member] | NYMEX [Member]
Derivatives, Fair Value [Line Items]
Year	2014
Index	NYMEX
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	22,000,000
Average Swap price per unit ($ per unit)	4.22
Swap [Member] | Natural Gas Sales (MMbtu) [Member] | 2014 [Member] | IFNPCR [Member]
Derivatives, Fair Value [Line Items]
Year	2014
Index	IFNPCR
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	60,500,000
Average Swap price per unit ($ per unit)	4.08
Swap [Member] | Natural Gas Sales (MMbtu) [Member] | 2015 [Member] | NYMEX [Member]
Derivatives, Fair Value [Line Items]
Year	2015
Index	NYMEX
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	25,600,000
Average Swap price per unit ($ per unit)	4.14
Swap [Member] | Natural Gas Sales (MMbtu) [Member] | 2015 [Member] | IFNPCR [Member]
Derivatives, Fair Value [Line Items]
Year	2015
Index	IFNPCR
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	7,300,000
Average Swap price per unit ($ per unit)	3.97
Swap [Member] | Oil Sales (Bbls) [Member] | 2014 [Member] | NYMEX WTI less ICE Brent Differential [Member]
Derivatives, Fair Value [Line Items]
Year	2014
Index	ICE Brent
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	600,000
Average Swap price per unit ($ per unit)	13.78
Swap [Member] | Oil Sales (Bbls) [Member] | 2014 [Member] | NYMEX WTI [Member]
Derivatives, Fair Value [Line Items]
Year	2014
Index	NYMEX WTI
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	8,100,000
Average Swap price per unit ($ per unit)	92.61
Swap [Member] | Oil Sales (Bbls) [Member] | 2014 [Member] | NYMEX WTI less LLS Differential [Member]
Derivatives, Fair Value [Line Items]
Index	LLS
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	500,000
Average Swap price per unit ($ per unit)	4.00
Swap [Member] | Oil Sales (Bbls) [Member] | 2015 [Member] | NYMEX WTI less ICE Brent Differential [Member]
Derivatives, Fair Value [Line Items]
Year	2015
Swap [Member] | Oil Sales (Bbls) [Member] | 2015 [Member] | NYMEX WTI [Member]
Derivatives, Fair Value [Line Items]
Index	NYMEX WTI
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	4,000,000
Average Swap price per unit ($ per unit)	87.64
Swap [Member] | Oil Sales (Bbls) [Member] | 2015 [Member] | BRENT ICE [Member]
Derivatives, Fair Value [Line Items]
Year	2015
Swap [Member] | Oil Sales (Bbls) [Member] | 2015 [Member] | NYMEX WTI less LLS Differential [Member]
Derivatives, Fair Value [Line Items]
Index	LLS
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	100,000
Average Swap price per unit ($ per unit)	4.00
Swap [Member] | QEP Marketing [Member] | 2014 [Member] | IFNPCR [Member]
Derivatives, Fair Value [Line Items]
Year	2014
Index	IFNPCR
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	2,900,000
Average Swap price per unit ($ per unit)	3.75
Swap [Member] | Purchased Gas and Oil Expense [Member] | 2014 [Member] | IFNPCR [Member]
Derivatives, Fair Value [Line Items]
Year	2014
Index	IFNPCR
Derivative Contracts - Volumes and Prices
Total Volume (in Bcf, Mbbl, millions of gallons, millions of MMBtu)	900,000
Average Swap price per unit ($ per unit)	3.82
Term Loan due 2017 [Member]
Derivatives, Fair Value [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	2.96%
First Term Loan Tranche [Member] | Interest Rate Swap [Member]
Derivative Contracts - Volumes and Prices
Variable Rate Received	One-month LIBOR
First Term Loan Tranche [Member] | Interest Rate Swap [Member] | QEP Resources [Member]
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional amount of interest rate derivatives	300.0
Derivative Contracts - Volumes and Prices
Notional amount of interest rate derivatives	300.0
Fixed Rate Paid (in hundredths)	1.07%
Second Term Loan Tranche [Member] | Interest Rate Swap [Member]
Derivative Contracts - Volumes and Prices
Variable Rate Received	One-month LIBOR
Second Term Loan Tranche [Member] | Interest Rate Swap [Member] | QEP Resources [Member]
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Notional amount of interest rate derivatives	300.0
Derivative Contracts - Volumes and Prices
Notional amount of interest rate derivatives	$ 300.0
Maturity	Mar. 31, 2017
Fixed Rate Paid (in hundredths)	0.86%

[1] Presented net of income tax benefit of $11.9 million during the three months ended March 31, 2013