Segment Information (Tables)

6 Months Ended

Jun. 30, 2012

Segment Information [Abstract]

Results from Continuing Operations by Reportable Segment

	Regulated		Regulated		All			Reconciling			Consolidated
(Thousands of Dollars)	Electric		Natural Gas		Other			Eliminations			Total
Three Months Ended June 30, 2012
Operating revenues from external customers	$	2,036,829	$	221,313	$	16,526		$	-		$	2,274,668
Intersegment revenues		297		219		-			(516	)		-
Total revenues	$	2,037,126	$	221,532	$	16,526		$	(516	)	$	2,274,668
Income (loss) from continuing operations	$	190,151	$	6,190	$	(13,266	)	$	-		$	183,075

	Regulated		Regulated		All			Reconciling			Consolidated
(Thousands of Dollars)	Electric		Natural Gas		Other			Eliminations			Total
Three Months Ended June 30, 2011
Operating revenues from external customers	$	2,128,397	$	291,538	$	18,287		$	-		$	2,438,222
Intersegment revenues		356		597		-			(953	)		-
Total revenues	$	2,128,753	$	292,135	$	18,287		$	(953	)	$	2,438,222
Income (loss) from continuing operations	$	162,482	$	6,596	$	(10,407	)	$	-		$	158,671

	Regulated		Regulated		All			Reconciling			Consolidated
(Thousands of Dollars)	Electric		Natural Gas		Other			Eliminations			Total
Six Months Ended June 30, 2012
Operating revenues from external customers	$	3,973,611	$	842,348	$	36,788		$	-		$	4,852,747
Intersegment revenues		599		718		-			(1,317	)		-
Total revenues	$	3,974,210	$	843,066	$	36,788		$	(1,317	)	$	4,852,747
Income (loss) from continuing operations	$	333,372	$	56,392	$	(22,920	)	$	-		$	366,844

	Regulated		Regulated		All			Reconciling			Consolidated
(Thousands of Dollars)	Electric		Natural Gas		Other			Eliminations			Total
Six Months Ended June 30, 2011
Operating revenues from external customers	$	4,158,369	$	1,056,887	$	39,506		$	-		$	5,254,762
Intersegment revenues		695		1,396		-			(2,091	)		-
Total revenues	$	4,159,064	$	1,058,283	$	39,506		$	(2,091	)	$	5,254,762
Income (loss) from continuing operations	$	317,119	$	65,193	$	(20,174	)	$	-		$	362,138