Schedule I - Condensed Financial Information of Parent Company - Related Party Transactions (Detail) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
(Payable to) Receivable from Related Party, Total	$ (8)	$ (13)
Money Pool Balance (included in cash and cash equivalents)		65
Conectiv Communications, Inc. [Member]
Related Party Transaction [Line Items]
(Payable to) Receivable from Related Party, Total	(4)	(4)
PHI Service Company [Member]
Related Party Transaction [Line Items]
(Payable to) Receivable from Related Party, Total	(4)	(10)
Other [Member]
Related Party Transaction [Line Items]
(Payable to) Receivable from Related Party, Total		1
Potomac Capital Investment Corporation (PCI) [Member]
Related Party Transaction [Line Items]
Payable to Related Party (non-current)	$ (498)	$ (494)

Money pool balance included in cash and cash equivalents.

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- Definition

Receivables to be collected from (obligations owed to) related parties, net as of the balance sheet date within one year where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of receivables to be collected from related parties net of obligations owed to related parties after one year or beyond the normal operating cycle, if longer where one party can exercise control or significant influence over another party including, but not limited to, affiliates, owners or officers and their immediate families and pension trusts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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- Definition

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.

+ References

No definition available.

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- Details

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- Details

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