Debt Maturity year

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Namespace Prefix:	pom
Data Type:	invest:dateStringItemType
Balance Type:	na
Period Type:	duration

- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of the required periodic payments applied to principal.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentPeriodicPaymentPrincipal
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Current period income tax expense or benefit pertaining to a gain (loss) on an extinguishment of debt.

+ References

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 26

-Paragraph 20

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 50

-Section 40

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6850294&loc=d3e12317-112629

+ Details

Name:	us-gaap_ExtinguishmentOfDebtGainLossIncomeTax
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Debt (Financing Activities) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended	9 Months Ended	0 Months Ended					1 Months Ended
	Jul. 08, 2010	Sep. 30, 2010	Sep. 30, 2010	Jul. 02, 2010 6.45% Senior Notes Due 2012 [Member]	Jul. 20, 2010 6.125% Senior Notes Due 2017 [Member]	Jul. 20, 2010 6.125% Senior Notes Due 2017 [Member]	Jul. 20, 2010 7.45% Senior Notes Due 2032 [Member]	Jul. 20, 2010 7.45% Senior Notes Due 2032 [Member]	Oct. 31, 2011 ACE [Member] Series 2002-1 Bonds [Member]	Jul. 31, 2011 ACE [Member] Series 2002-1 Bonds [Member]	Oct. 31, 2011 ACE [Member] Series 2003-1 Bonds [Member]	Jul. 31, 2011 ACE [Member] Series 2003-1 Bonds [Member]
Redemption of outstanding debt	$ 110			$ 640	$ 129		$ 65
Debt interest percentage				6.45%	6.125%	6.125%	7.45%	7.45%
Debt maturity year				2012		2017		2032
Pre-tax extinguishment of debt		120	15
Funding made principal payments									$ 8	$ 6	$ 3	$ 2