Approximately amount of MW's already installed

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- Definition

Estimated Project Total Costs

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- Definition

Estimated Total Cost Of Owned Assets Phase

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- Definition

Increase of MW nominal capacity after completion of upgrades.

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- Definition

Investment in projects, amount

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- Definition

Long Term Purchase Commitment Amount High Range

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Long Term Purchase Commitment Amount Low Range

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- Definition

Number of MW of gas fired peaking capacity to be built.

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- Definition

Number of MW of installation of solar generation on land and building

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- Definition

Number Of MW Of Solar Capacity

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- Definition

Number of MW of solar generation on existing utility poles being installed.

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- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 15

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 17

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

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Commitments And Contingent Liabilities (New Generation And Development) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended		12 Months Ended			9 Months Ended					9 Months Ended	12 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2011 mW	Sep. 30, 2011 Power [Member] Period 2012-2013 [Member] Kearny Site [Member] PJM Interconnection Capital Additions [Member] mW	Sep. 30, 2011 Power [Member] Period 2013-2015 [Member] PJM Interconnection Capital Additions [Member] mW	Sep. 30, 2011 Power [Member] Peach Bottom Units [Member] Nuclear Up Rate Capital Additions [Member] mW	Sep. 30, 2011 PSE&G [Member] Solar Capital Additions [Member]	Sep. 30, 2011 Power [Member] PJM Interconnection Capital Additions [Member]	Sep. 30, 2011 Power [Member] Connecticut Capital Additions [Member]	Mar. 31, 2011 Power [Member] Connecticut Capital Additions [Member] mW	Sep. 30, 2011 Power [Member] Nuclear Steam Path Capital Additions [Member]	Dec. 31, 2011 Power [Member] Nuclear Steam Path Capital Additions [Member] mW	Sep. 30, 2011 Power [Member]	Sep. 30, 2010 Power [Member]	Sep. 30, 2011 PSE&G [Member] mW cubicFeet	Sep. 30, 2010 PSE&G [Member]
Long-term Purchase Commitment [Line Items]
Approximate amount committed	$ 896					$ 400					$ 192
Increase of MW nominal capacity after completion of upgrades						133						18
Total expenditures to date	1,479	1,517				28	164	148	99		94		530	579	939	871
Number of MW of gas fired peaking capacity to be built				178	267					130
Number of MW of solar generation on existing utility poles being installed															40
Number of MW of installation of solar generation on land and building															40
Approximately amount of MW's already installed															23
Estimated solar project cost, total	264
Estimated total cost of land and buildings owned phase	189
Number of MW of solar capacity placed into service			23
Long term purchase commitment amount low range								250	140
Approximate amount committed-high end of range								300	150
Investment in projects, amount							$ 116