Fair Value Measurements (Narrative) (Detail) (USD $)	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011
Assets, Fair Value Disclosure, Recurring	$ 1,800,000,000		$ 1,500,000,000
Fair value option of contractual principal outstanding		550,000,000
Nonrecurring fair value of leased assets		50,000,000
Current liabilities, fair value	51,000,000	131,000,000
Power [Member]
Current liabilities, fair value	51,000,000	124,000,000
PSEG [Member]
Current liabilities, fair value		50,000,000
NDT Funds [Member] \| Power [Member]
Cash Held in NDT Fund	$ 8,000,000

The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

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Fair values as of the balance sheet date of all liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments, and which are expected to be extinguished or otherwise disposed of within a year or the normal operating cycle, if longer, net of the effects of master netting arrangements.

+ References

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+ Details