Business acquisition cost of acquired entity transaction costs after tax.

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Decrease in current assets due to business acquisition purchase price allocation.

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- Definition

Decrease in goodwill due to business acquisition purchase price allocation.

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- Definition

Exchange ratio to calculate number of shares to be received by acquiree company on merger.

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- Definition

Expenses related to merger settlements approved by regulatory agencies.

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Increase in goodwill due to business acquisition purchase Price Allocation.

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- Definition

Inventory adjustments net of tax.

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- Definition

Merger related expenses.

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- Definition

Merger.

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The aggregate amount assigned to a major class of finite-lived intangible assets acquired either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 44
-Subparagraph a(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16265-109275

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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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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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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 59
-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.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=6909708&loc=d3e1043-128460

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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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- Definition

Certain changes made in the current period to the value and amount of inventory reported.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6386783&loc=d3e4492-108314

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Chapter 3
-Section A
-Paragraph 9
-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 SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 6
-Subparagraph b
-Article 5

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Merger (Details Textuals) (USD $) In Millions, except Share data	3 Months Ended	6 Months Ended			6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2011	Feb. 25, 2011	Jun. 30, 2011 Land easements and computer equipment [Member]	Jun. 30, 2011 Allegheny Energy Inc	Jun. 30, 2010 Allegheny Energy Inc	Jun. 30, 2011 Allegheny Energy Inc Pre-tax [Member]	Jun. 30, 2010 Allegheny Energy Inc Pre-tax [Member]	Jun. 30, 2011 Allegheny Energy Inc Pre-tax [Member]	Jun. 30, 2010 Allegheny Energy Inc Pre-tax [Member]	Jun. 30, 2011 Pre-tax [Member]	Jun. 30, 2010 Pre-tax [Member]	Jun. 30, 2011 Pre-tax [Member]	Jun. 30, 2010 Pre-tax [Member]	Jun. 30, 2011 Net of Tax [Member]	Jun. 30, 2010 Net of Tax [Member]	Jun. 30, 2011 Net of Tax [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Fair value of intangible assets acquired				$ 169
Business Acquisition [Line Items]
Merger related Expenses					56		7	7	89	21							47
Merger transaction costs					72	15					7	11	90	39	5	5
Merger integration costs											10		85		6		66
Merger (Textuals) [Abstract]
Exchange ratio			0.667
Increase in noncurrent assets		85
Decrease in current assets		15
Decrease in goodwill		71
Allegheny's after-tax merger costs	4	56
Expenses related to merger settlements approved by regulatory agencies		32
Inventory valuation adjustment	67	67
Inventory valuation adjustment, net of tax	$ 42	$ 42