Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2011

Asset Retirement Obligation [Abstract]

Changes in ARO

Changes in Questar's AROs from the Consolidated Balance Sheets were as follows:

	2011			2010
	(in millions)
AROs at beginning of year	$	60.9		$	65.0
Accretion	3.0			2.9
Liabilities incurred	1.5			1.3
Revisions	0.8			(8.3		)
Liabilities settled	(2.4		)	—
AROs at end of year	$	63.8		$	60.9

Asset Retirement Obligations by line of business

Questar's consolidated AROs by line of business are summarized in the table below:

	December 31,
	2011		2010
	(in millions)
Wexpro	$	60.3	$	56.0
Questar Pipeline	2.8		4.1
Questar Gas	0.7		0.8
Total	$	63.8	$	60.9