Restructuring Costs (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			$ 8.0
Restructuring and Related Cost, Cost Incurred to Date			7.9
Restructuring Charges	0.3	0.3	0.9	5.3
Increase (Decrease) in Restructuring Liability [Roll Forward]
Balance at Beginning of Period			1.0
Restructuring Reserve, Accrual Adjustment			0.9
Costs paid or otherwise settled			(1.9)
Balance at End of Period	0		0
Number of regional offices created			1
One-time Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			3.6
Restructuring and Related Cost, Cost Incurred to Date			3.6
Restructuring Charges	0.1	0.2	0.5	2.1
Employee Relocation [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			3.8
Restructuring and Related Cost, Cost Incurred to Date			3.7
Restructuring Charges	0.2	0.1	0.4	3.2
Termination of Lease [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0.6
Restructuring and Related Cost, Cost Incurred to Date			0.6
Restructuring Charges	0	0	0	0
QEP Energy [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			7.6
Restructuring and Related Cost, Cost Incurred to Date			7.5
Restructuring Charges	0.2	0.3	0.7	5.3
Increase (Decrease) in Restructuring Liability [Roll Forward]
Balance at Beginning of Period			1.0
Restructuring Reserve, Accrual Adjustment			0.7
Costs paid or otherwise settled			(1.7)
Balance at End of Period	0		0
QEP Energy [Member] | One-time Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			3.3
Restructuring and Related Cost, Cost Incurred to Date			3.3
Restructuring Charges	0.1	0.2	0.4	2.1
QEP Energy [Member] | Employee Relocation [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			3.7
Restructuring and Related Cost, Cost Incurred to Date			3.6
Restructuring Charges	0.1	0.1	0.3	3.2
QEP Energy [Member] | Termination of Lease [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0.6
Restructuring and Related Cost, Cost Incurred to Date			0.6
Restructuring Charges	0	0	0	0
QEP Field Services [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0.1
Restructuring and Related Cost, Cost Incurred to Date			0.1
Restructuring Charges	0.1	0	0.1	0
Increase (Decrease) in Restructuring Liability [Roll Forward]
Balance at Beginning of Period			0
Restructuring Reserve, Accrual Adjustment			0.1
Costs paid or otherwise settled			(0.1)
Balance at End of Period	0		0
QEP Field Services [Member] | One-time Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0
Restructuring and Related Cost, Cost Incurred to Date			0
Restructuring Charges	0	0	0	0
QEP Field Services [Member] | Employee Relocation [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0.1
Restructuring and Related Cost, Cost Incurred to Date			0.1
Restructuring Charges	0.1	0	0.1	0
QEP Field Services [Member] | Termination of Lease [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0
Restructuring and Related Cost, Cost Incurred to Date			0
Restructuring Charges	0	0	0	0
QEP Marketing [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0.3
Restructuring and Related Cost, Cost Incurred to Date			0.3
Restructuring Charges	0	0	0.1	0
Increase (Decrease) in Restructuring Liability [Roll Forward]
Balance at Beginning of Period			0
Restructuring Reserve, Accrual Adjustment			0.1
Costs paid or otherwise settled			(0.1)
Balance at End of Period	0		0
QEP Marketing [Member] | One-time Termination Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0.3
Restructuring and Related Cost, Cost Incurred to Date			0.3
Restructuring Charges	0	0	0.1	0
QEP Marketing [Member] | Employee Relocation [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0
Restructuring and Related Cost, Cost Incurred to Date			0
Restructuring Charges	0	0	0	0
QEP Marketing [Member] | Termination of Lease [Member]
Restructuring Cost and Reserve [Line Items]
Estimated restructuring costs			0
Restructuring and Related Cost, Cost Incurred to Date			0
Restructuring Charges	$ 0	$ 0	$ 0	$ 0