Report of Business Segments (Tables)

9 Months Ended

Sep. 30, 2011

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

 The following tables summarize the results of the Company's business segments for the three and nine months ended September 30, 2011 and 2010.

			Transportation		Gathering
Three Months Ended	Electric		and		and					Other
September 30, 2011	Utility		Storage		Processing		Marketing			Operations			Eliminations			Total
(In millions)
Operating revenues	$	774.8	$	103.7	$	304.9	$	160.0		$	—		$	(131.3	)	$	1,212.1
Cost of goods sold	334.7		58.6		233.2		163.1			—			(131.1		)	658.5
Gross margin on revenues	440.1		45.1		71.7		(3.1		)	—			(0.2		)	553.6
Other operation and maintenance	108.3		13.7		28.8		1.8			(4.4		)	(0.8		)	147.4
Depreciation and amortization	54.9		5.2		13.4		—			3.6			—			77.1
Impairment of assets	—		—		5.0		—			—			—			5.0
Taxes other than income	18.2		3.5		1.8		0.1			0.8			—			24.4
Operating income (loss)	$	258.7	$	22.7	$	22.7	$	(5.0	)	$	—		$	0.6		$	299.7
Total assets	$	6,451.8	$	2,474.1	$	1,189.1	$	67.7		$	3,149.8		$	(4,953.7	)	$	8,378.8

			Transportation		Gathering
Three Months Ended	Electric		and		and					Other
September 30, 2010	Utility		Storage		Processing		Marketing			Operations			Eliminations			Total
(In millions)
Operating revenues	$	723.0	$	103.5	$	243.1	$	206.5		$	—		$	(150.7	)	$	1,125.4
Cost of goods sold	311.2		64.8		178.9		207.6			—			(149.9		)	612.6
Gross margin on revenues	411.8		38.7		64.2		(1.1		)	—			(0.8		)	512.8
Other operation and maintenance	110.8		11.6		22.0		1.8			(3.2		)	(0.6		)	142.4
Depreciation and amortization	53.1		5.2		12.6		—			2.8			—			73.7
Taxes other than income	16.9		3.3		1.4		0.1			0.8			—			22.5
Operating income (loss)	$	231.0	$	18.6	$	28.2	$	(3.0	)	$	(0.4	)	$	(0.2	)	$	274.2
Total assets	$	5,882.7	$	1,670.0	$	941.1	$	105.4		$	2,834.4		$	(3,906.2	)	$	7,527.4

			Transportation		Gathering
Nine Months Ended	Electric		and		and					Other
September 30, 2011	Utility		Storage		Processing		Marketing			Operations			Eliminations			Total
(In millions)
Operating revenues	$	1,765.6	$	311.9	$	860.7	$	526.4		$	—		$	(433.9	)	$	3,030.7
Cost of goods sold	808.4		192.1		640.4		532.8			—			(431.9		)	1,741.8
Gross margin on revenues	957.2		119.8		220.3		(6.4		)	—			(2.0		)	1,288.9
Other operation and maintenance	324.3		35.8		81.9		5.9			(13.3		)	(2.3		)	432.3
Depreciation and amortization	158.8		16.4		40.4		—			10.2			—			225.8
Impairment of assets	—		—		5.0		—			—			—			5.0
Taxes other than income	56.1		11.1		5.3		0.3			3.2			—			76.0
Operating income (loss)	$	418.0	$	56.5	$	87.7	$	(12.6	)	$	(0.1	)	$	0.3		$	549.8
Total assets	$	6,451.8	$	2,474.1	$	1,189.1	$	67.7		$	3,149.8		$	(4,953.7	)	$	8,378.8

			Transportation		Gathering
Nine Months Ended	Electric		and		and					Other
September 30, 2010	Utility		Storage		Processing		Marketing			Operations			Eliminations			Total
(In millions)
Operating revenues	$	1,679.8	$	311.7	$	726.4	$	641.2		$	—		$	(470.7	)	$	2,888.4
Cost of goods sold	792.8		191.9		527.5		644.8			—			(467.8		)	1,689.2
Gross margin on revenues	887.0		119.8		198.9		(3.6		)	—			(2.9		)	1,199.2
Other operation and maintenance	305.9		35.2		66.8		6.6			(10.8		)	(2.7		)	401.0
Depreciation and amortization	153.4		16.0		37.5		—			8.3			—			215.2
Taxes other than income	51.8		10.6		4.9		0.3			2.9			—			70.5
Operating income (loss)	$	375.9	$	58.0	$	89.7	$	(10.5	)	$	(0.4	)	$	(0.2	)	$	512.5
Total assets	$	5,882.7	$	1,670.0	$	941.1	$	105.4		$	2,834.4		$	(3,906.2	)	$	7,527.4