Regulatory Assets and Liabilities (Tables)

3 Months Ended

Mar. 31, 2013

Regulatory Assets and Liabilities Disclosure [Abstract]

Regulatory Assets Included on the Consolidated Balance Sheets

Regulatory assets included on the consolidated balance sheets are:

(in millions)	March 31, 2013		December 31, 2012
Current:
Regulatory balancing accounts	$	624	$	502
Energy derivatives	48		70
Total Current	672		572
Long-term:
Deferred income taxes, net	2,718		2,663
Pensions and other postretirement benefits	1,539		1,550
Energy derivatives	974		900
Unamortized investments, net	487		507
Unamortized loss on reacquired debt	222		228
Nuclear-related investment, net	138		141
Regulatory balancing accounts	76		73
Other	364		360
Total Long-term	6,518		6,422
Total Regulatory Assets	$	7,190	$	6,994

Regulatory Liabilities Included on the Consolidated Balance Sheets

Regulatory liabilities included on the consolidated balance sheets are:

(in millions)	March 31, 2013		December 31, 2012
Current:
Regulatory balancing accounts	$	383	$	484
Other	60		52
Total Current	443		536
Long-term:
Costs of removal	2,769		2,731
Asset Retirement Obligations	1,538		1,385
Regulatory balancing accounts	1,156		1,091
Other	7		7
Total Long-term	5,470		5,214
Total Regulatory Liabilities	$	5,913	$	5,750