Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2012

Asset Retirement Obligation [Abstract]

Changes in ARO

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

	Year Ended December 31,
	2012			2011
	(in millions)
AROs at beginning of year	$	63.8		$	60.9
Accretion	3.4			3.0
Liabilities incurred	3.1			1.5
Revisions in estimated cash flows	(1.7		)	0.8
Liabilities settled	(1.4		)	(2.4		)
AROs at end of year	$	67.2		$	63.8

Asset Retirement Obligations by line of business

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

	December 31,
	2012		2011
	(in millions)
Questar Gas	$	0.5	$	0.7
Wexpro	64.6		60.3
Questar Pipeline	2.1		2.8
Total	$	67.2	$	63.8