Basis of Presentation of Interim Financial Statements (Tables)

3 Months Ended

Mar. 31, 2014

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Cost of sales detail

The details of Questar's consolidated cost of sales are as follows:

	3 Months Ended						12 Months Ended
	March 31,						March 31,
	2014			2013			2014			2013
	(in millions)
Questar Gas
Gas purchases	$	92.7		$	103.3		$	176.0		$	146.0
Operator service fee	89.1			72.8			310.9			281.1
Transportation and storage	22.1			22.0			80.2			81.0
Gathering	4.9			4.6			19.1			19.0
Royalties	17.3			11.1			50.5			32.9
Storage withdrawal, net	33.0			28.8			3.4			3.3
Purchased-gas account adjustment	(5.6		)	46.7			(30.3		)	19.4
Other	1.1			1.3			4.8			5.0
Total Questar Gas cost of natural gas sold	254.6			290.6			614.6			587.7
Elimination of Questar Gas cost of natural gas sold - affiliated parties	(108.2		)	(92.1		)	(387.0		)	(355.8		)
Total Questar Gas cost of natural gas sold - unaffiliated parties	146.4			198.5			227.6			231.9
Questar Pipeline
Total Questar Pipeline cost of sales	1.7			1.2			6.6			7.4
Other cost of sales	0.1			—			0.2			—
Total cost of sales	$	148.2		$	199.7		$	234.4		$	239.3