Preferred and Preference Stock of Utility (Tables)

12 Months Ended

Dec. 31, 2011

Preferred and Preference Stock of Utility [Abstract]

Preferred and Preference Stock of Utility Not Subject to Mandatory Redemption

Preferred stock and preference stock is:

	Shares Outstanding	Redemption Price		December 31,
(in millions, except shares and per-share amounts)				2011			2010
Cumulative preferred stock
$25 par value:
4.08% Series	650,000	$	25.50	$	16		$	16
4.24% Series	1,200,000	25.80		30			30
4.32% Series	1,653,429	28.75		41			41
4.78% Series	1,296,769	25.80		33			33
Preference stock
No par value:
4.90% Series A (variable and noncumulative)	4,000,000	100.00		400			400
6.125% Series B (noncumulative)	2,000,000	100.00		200			200
6.00% Series C (noncumulative)	2,000,000	100.00		200			200
6.50% Series D (cumulative)	1,250,000	100.00		125			—
				1,045			920
Less issuance costs				(16		)	(13		)
Total				$	1,029		$	907