2.2.0.25falsefalse132 - Disclosure - Risk Management Activities and Fair Value Measurements - Additional Information (Detail)truefalseIn Millionsfalse1falsefalseUSDfalsefalse3/31/2011
USD ($)
$eol_PE1341----1110-Q0005_STD_0_20110331_0http://www.sec.gov/CIK0000080424instant2011-03-31T00:00:000001-01-01T00:00:00iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170sharesStandardhttp://www.xbrl.org/2003/instanceshares0USDUSD$2falsefalseUSDfalsefalse6/30/2010
USD ($)
$eol_PE1341----1110-Q0005_STD_0_20100630_0http://www.sec.gov/CIK0000080424instant2010-06-30T00:00:000001-01-01T00:00:00iso4217_USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170sharesStandardhttp://www.xbrl.org/2003/instanceshares0USDUSD$5false0us-gaap_DerivativeNetLiabilityPositionAggregateFairValueus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse146000000146falsetruefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain or loss on that instrument.Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44D
-Subparagraph b
falsefalse6false0pg_LongTermDebtFairValueDisclosurepgfalsecreditinstantLong-Term Debt, Fair Value Disclosurefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse2299600000022996falsetruefalsefalsefalse2truefalsefalse2307200000023072falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLong-Term Debt, Fair Value DisclosureNo authoritative reference available.falsefalse22Risk Management Activities and Fair Value Measurements - Additional Information (Detail) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue
