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General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 4 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Chapter 4 -Paragraph 5A falsefalseSelling, general and administrative expenses7false0wpz_OtherIncomeExpenseNetwpzfalsecreditdurationOther Income Expense Net.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegatedtotal1truefalsefalse-13000000-13falsefalsefalsefalsefalse2truefalsefalse-1000000-1[1]falsefalsefalsefalsefalse3truefalsefalse-22000000-22falsefalsefalsefalsefalse4falsefalsefalse00 [1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryOther Income Expense Net.No authoritative reference available.truefalseOther income - net8false0wpz_SegmentCostsAndExpenseswpzfalsedebitdurationSegment costs and expenses.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse980000000980falsefalsefalsefalsefalse2truefalsefalse884000000884[1]falsefalsefalsefalsefalse3truefalsefalse31380000003138falsefalsefalsefalsefalse4truefalsefalse24460000002446[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetarySegment costs and expenses.No authoritative reference available.falsefalseSegment costs and expenses9false0wpz_GeneralCorporateExpensewpzfalsedebitdurationGeneral corporate expenses.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse3000000030falsefalsefalsefalsefalse2truefalsefalse2700000027[1]falsefalsefalsefalsefalse3truefalsefalse9300000093falsefalsefalsefalsefalse4truefalsefalse7900000079[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryGeneral corporate expenses.No authoritative reference available.truefalseGeneral corporate expenses10true0us-gaap_OperatingIncomeLossAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalse4falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseOperating income:11false0us-gaap_OperatingIncomeLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse317000000317falsefalsefalsefalsefalse2truefalsefalse290000000290[1]falsefalsefalsefalsefalse3truefalsefalse986000000986falsefalsefalsefalsefalse4truefalsefalse763000000763[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe net result for the period of deducting operating expenses from operating revenues.No authoritative reference available.falsefalseTotal operating income12false0us-gaap_IncomeLossFromEquityMethodInvestmentsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse2400000024falsefalsefalsefalsefalse2truefalsefalse3000000030[1]falsefalsefalsefalsefalse3truefalsefalse7700000077falsefalsefalsefalsefalse4truefalsefalse5100000051[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. Such amount typically reflects adjustments similar to those made in preparing consolidated statements, including adjustments to eliminate intercompany gains and losses, and to amortize, if appropriate, any difference between cost and underlying equity in net assets of the investee at the date of investment.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 19 -Subparagraph c Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 7 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 6 -Subparagraph b falsefalseEquity earnings13false0wpz_InterestAccruedThirdPartywpzfalsecreditdurationInterest accrued - 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net18false0wpz_IncomeBeforeIncomeTaxeswpzfalsecreditdurationIncome before income taxes.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse254000000254falsefalsefalsefalsefalse2truefalsefalse279000000279[1]falsefalsefalsefalsefalse3truefalsefalse816000000816falsefalsefalsefalsefalse4truefalsefalse688000000688[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncome before income taxes.No authoritative reference available.falsefalseIncome before income taxes19false0us-gaap_IncomeTaxExpenseBenefitus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse10000001falsefalsefalsefalsefalse2truefalsefalse10000001[1]falsefalsefalsefalsefalse3truefalsefalse10000001falsefalsefalsefalsefalse4truefalsefalse40000004[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph a, b truefalseProvision for income taxes20false0us-gaap_ProfitLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse253000000253falsefalsefalsefalsefalse2truefalsefalse278000000278[1]falsefalsefalsefalsefalse3truefalsefalse815000000815falsefalsefalsefalsefalse4truefalsefalse684000000684[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) falsefalseNet income21false0us-gaap_NetIncomeLossAttributableToNoncontrollingInterestus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse50000005falsefalsefalsefalsefalse2truefalsefalse70000007[1]falsefalsefalsefalsefalse3truefalsefalse1600000016falsefalsefalsefalsefalse4truefalsefalse2000000020[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe portion of net income (loss) attributable to the noncontrolling interest (if any) deducted in order to derive the portion attributable to the parent.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 truefalseLess: Net income attributable to noncontrolling interests22false0us-gaap_NetIncomeLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse248000000248falsefalsefalsefalsefalse2truefalsefalse271000000271[1]falsefalsefalsefalsefalse3truefalsefalse799000000799falsefalsefalsefalsefalse4truefalsefalse664000000664[1]falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. 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