Condensed Consolidated Statements of Financial Position (Unaudited) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012		Jun. 30, 2012
Current assets
Cash and cash equivalents	$ 184		$ 131		$ 87
Short-term investments	42		58		61
Receivables
Energy marketing receivables	608		677		347
Gas, unbilled and other receivables	437		686		349
Less allowance for uncollectible accounts	41		28		39
Total receivables	1,004		1,335		657
Inventories, net	530		708		549
Regulatory assets	120		145		146
Derivative instruments	113		130		181
Other current assets	70		161		199
Total current assets	2,063		2,668		1,880
Long-term assets and other deferred debits
Property, plant and equipment	10,761		10,478		10,091
Less accumulated depreciation	2,264		2,131		2,004
Property, plant and equipment, net	8,497		8,347		8,087
Goodwill	1,883		1,837		1,813
Regulatory assets	898		944		1,083
Intangible assets	184		96		100
Derivative instruments	17		14		45
Other	253		235		221
Total long-term assets and other deferred debits	11,732		11,473		11,349
Total assets	13,795	[1]	14,141	[2]	13,229	[1]
Current liabilities
Energy marketing trade payable	628		611		383
Short-term debt	521		1,377		731
Accounts payable - trade	344		334		248
Regulatory liabilities	216		161		137
Accrued expenses	170		140		138
Customer deposit and credit balances	114		143		139
Temporary LIFO liquidation	84				41
Accrued environmental remediation liabilities	62		57		59
Accrued regulatory infrastructure program costs	55		121		158
Derivative instruments	33		33		58
Current portion of long-term debt and capital leases			226		231
Other current liabilities	122		135		137
Total current liabilities	2,349		3,338		2,460
Long-term liabilities and other deferred credits
Long-term debt	3,819		3,327		3,334
Accumulated deferred income taxes	1,567		1,588		1,509
Regulatory liabilities	1,510		1,477		1,453
Accrued environmental remediation liabilities	406		387		371
Accrued retiree welfare benefits	264		268		296
Accrued pension obligations	246		240		221
Derivative instruments	6		6		8
Other long-term liabilities and other deferred credits	73		75		148
Total long-term liabilities and other deferred credits	7,891		7,368		7,340
Total liabilities and other deferred credits	10,240		10,706		9,800
Equity
Common stock, $5 par value; 750,000,000 shares authorized: outstanding: 118,560,687 shares at June 30, 2013, 117,855,075 shares at December 31, 2012 and 117,505,440 shares at June 30, 2012	594		590		589
Additional paid in capital	2,035		2,014		2,003
Retained earnings	1,127		1,035		1,035
Accumulated other comprehensive loss	(209)		(218)		(207)
Treasury shares, at cost: 216,523 shares at June 30, 2013 and December 31, 2012 and June 30, 2012	(8)		(8)		(8)
Total common shareholders’ equity	3,539		3,413		3,412
Noncontrolling interest	16		22		17
Total equity	3,555		3,435		3,429
Total liabilities and equity	$ 13,795		$ 14,141		$ 13,229

[1] Identifiable assets are those used in each segment's operations.

[2] Identifiable assets are those assets used in each segment's operations.