Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2011

Earnings Per Common Share Attributable To Questar [Abstract]

Reconciliation of the components of basic and diluted shares in EPS calculations

Changes in Questar's ARO from the Consolidated Balance Sheets for the six months ended June 30 were as follows:

	2011	2010
	(in millions)
ARO liability at December 31	$60.9	$65.0
Accretion	1.5	1.4
Liabilities incurred	0.6	0.4
Revisions	2.4	(8.3)
Liabilities settled	(0.2)	(0.2)
ARO liability at June 30	$65.2	$58.3