CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income (loss)		$ (149.4)	$ 784.4	$ 159.4
Other comprehensive income, (loss), net of tax:
Reclassification of previously deferred derivative (gains) losses	[1]	0.0	0.0	(77.6)
Pension and other postretirement plans adjustments:
Current year net actuarial gain (loss)	[2]	(0.5)	(13.6)	13.5
Amortization of net actuarial loss	[3]	0.3	0.5	1.5
Amortization of net prior service cost	[4]	8.2	9.7	3.3
Current year prior service cost	[5]	(0.6)	0.0	0.0
Net curtailment and settlements cost incurred	[6]	4.5	5.6	0.0
Total pension and other postretirement plans adjustments		11.9	2.2	18.3
Other comprehensive income (loss)		11.9	2.2	(59.3)
Comprehensive income (loss) attributable to QEP		$ (137.5)	$ 786.6	$ 100.1

[1] Presented net of income tax benefit of $45.9 million for the year ended December 31, 2013.

[2] Presented net of income tax benefit of $0.3 million for the year ended December 31, 2015, net of income tax benefit of $8.5 million for the year ended December 31, 2014, and net of income tax expense of $8.3 million for the year ended December 31, 2013

[3] Presented net of income tax expense of $0.2 million, $0.3 million, and $0.9 million during the years ended December 31, 2015, 2014, and 2013, respectively.

[4] Presented net of income tax expense of $4.9 million, $6.0 million, and $2.1 million during the years ended December 31, 2015, 2014, and 2013, respectively.

[5] Presented net of income tax benefit of $0.3 million for the year ended December 31, 2015.

[6] Presented net of income tax expense of $2.6 million and $3.5 million for the years ended December 31, 2015 and 2014, respectively.