Consolidated Balance Sheet (Parenthetical) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Accounts receivable-customers, allowance for uncollectible accounts	$ 84	$ 76
Other receivables, allowance for uncollectible accounts	9	8
Non-utility property, accumulated depreciation	55	51
Intangible assets, accumulated amortization	3	3
CECONY [Member]
Accounts receivable-customers, allowance for uncollectible accounts	75	68
Other receivables, allowance for uncollectible accounts	8	7
Non-utility property, accumulated depreciation	$ 23	$ 22