CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
REVENUES
Natural gas sales	$ 194.8	$ 170.3	$ 610.5	$ 470.4
Oil sales	253.8	117.7	656.3	335.7
NGL sales	71.3	67.5	215.0	247.0
Gathering, processing and other	46.9	46.3	135.1	141.9
Purchased gas, oil and NGL sales	206.0	140.6	603.4	449.9
Total Revenues	772.8	542.4	2,220.3	1,644.9
OPERATING EXPENSES
Purchased gas, oil and NGL expense	205.0	142.6	608.8	455.9
Lease operating expense	45.0	42.2	127.4	122.8
Natural gas, oil and NGL transportation and other handling costs	34.5	36.3	105.8	111.5
Gathering, processing and other	22.4	22.1	66.5	66.4
General and administrative	49.3	41.7	136.2	114.5
Production and property taxes	42.5	24.3	117.7	68.4
Depreciation, depletion and amortization	253.1	234.6	757.1	648.3
Exploration expenses	1.8	2.2	9.5	6.3
Impairment	3.8	9.0	4.0	70.9
Total Operating Expenses	657.4	555.0	1,933.0	1,665.0
Net (loss) gain from asset sales	12.8	0	113.0	1.5
OPERATING INCOME	128.2	(12.6)	400.3	(18.6)
Realized and unrealized (losses) gains on derivative contracts (See Note 8)	(27.8)	36.1	51.6	334.7
Interest and other income	4.0	(0.2)	9.1	2.4
Income from unconsolidated affiliates	0.8	2.3	3.7	5.6
Loss from early extinguishment of debt	0	0	0	(0.6)
Interest expense	(41.7)	(30.0)	(122.5)	(82.9)
(LOSS) INCOME BEFORE INCOME TAXES	63.5	(4.4)	342.2	240.6
Income tax benefit (provision)	(22.4)	2.3	(125.0)	(86.5)
NET (LOSS) INCOME	41.1	(2.1)	217.2	154.1
Net income attributable to noncontrolling interest	(3.8)	(1.0)	(5.8)	(2.7)
NET (LOSS) INCOME ATTRIBUTABLE TO QEP	$ 37.3	$ (3.1)	$ 211.4	$ 151.4
Earnings Per Common Share Attributable to QEP
Basic total (in dollars per share)	$ 0.21	$ (0.02)	$ 1.18	$ 0.85
Diluted total (in dollars per share)	$ 0.21	$ (0.02)	$ 1.18	$ 0.85
Weighted-average common shares outstanding
Used in basic calculation (in shares)	179.3	177.9	179.2	177.6
Used in diluted calculation (in shares)	179.5	177.9	179.4	178.6
Dividends per common share (in dollars per share)	$ 0.02	$ 0.02	$ 0.06	$ 0.06