Leasing Activities (Income Recognized From Cross-Border Energy Lease Investments) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Leases [Abstract]
Pre-tax income from PHI's cross-border energy lease investments (included in Other Revenue)	$ 5	$ 13
Non-cash charge to reduce carrying value of PHI's cross-border energy lease investments	(373)
Pre-tax (loss) income from PHI's cross-border energy lease investments after adjustment	(368)	13
Income tax (benefit) expense related to PHI's cross-border energy lease investments, including interest expense on uncertain tax positions	(48)	1
Net (loss) income from PHI's cross-border energy lease investments	$ (320)	$ 12

Leveraged Leases Income Statement Income From Leveraged Leases After Adjustment

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- Definition

Non Cash Charge To Reduce Carrying Value Of Leveraged Leases

+ References

No definition available.

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- Definition

Pretax lease income allocated in proportionate amounts from unearned income.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 840

-SubTopic 30

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=7662751&loc=d3e45152-112736

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- Definition

The tax effect from the current year income from arrangements meeting the criteria for classification as a leveraged lease.

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- Definition

The total recognized during the period for income on leases meeting the criteria for classification as leveraged leases.

+ References

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