1.0.0.3 false 1000 - UNAUDITED CONDENSED CONSOLIDATED STATEMENTS of INCOME (USD $) In Millions, except Share data false 1 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 2 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 3 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 false 4 $ false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 5 Operating revenues 3 us-gaap_UtilityRevenue us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 2312000000 2312 false false 2 true true 2244000000 2244 false false 3 true true 4754000000 4754 false false 4 true true 4310000000 4310 false false No definition available. No authoritative reference available. false 6 Operating expenses 3 us-gaap_OperatingExpensesAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 7 Fuel used in electric generation 4 us-gaap_FuelCosts us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 826000000 826 false false 2 false true 696000000 696 false false 3 false true 1780000000 1780 false false 4 false true 1393000000 1393 false false No definition available. No authoritative reference available. false 8 Purchased power 4 us-gaap_CostOfPurchasedPower us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 257000000 257 false false 2 false true 330000000 330 false false 3 false true 474000000 474 false false 4 false true 562000000 562 false false No definition available. No authoritative reference available. false 9 Operation and maintenance 4 pgn_OperatingMaintenanceExpense pgn false debit duration monetary The amount of operating expense for the period for maintenance, repairs and operations. false false false false false false false false false 1 false true 484000000 484 false false 2 false true 488000000 488 false false 3 false true 937000000 937 false false 4 false true 931000000 931 false false The amount of operating expense for the period for maintenance, repairs and operations. No authoritative reference available. false 10 Depreciation, amortization and accretion 4 pgn_DepreciationAmortizationAndAccretionIncomeStatement pgn false debit duration monetary The current period expense charged against earnings on long-lived, physical assets used in the normal conduct of business and... false false false false false false false false false 1 false true 226000000 226 false false 2 false true 208000000 208 false false 3 false true 506000000 506 false false 4 false true 414000000 414 false false The current period expense charged against earnings on long-lived, physical assets used in the normal conduct of business and not intended for resale to allocate or recognize the cost of assets over their useful lives; to record the reduction in book value of an intangible asset over the benefit period of such asset; or to record accretion expense in each subsequent period to recognize asset or liability growth resulting from the passage of time. No authoritative reference available. false 11 Taxes other than on income 4 us-gaap_TaxesExcludingIncomeAndExciseTaxes us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 130000000 130 false false 2 false true 125000000 125 false false 3 false true 273000000 273 false false 4 false true 246000000 246 false false No definition available. No authoritative reference available. false 12 Other 4 us-gaap_OtherCostAndExpenseOperating us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 10000000 10 false false 2 false true -9000000 -9 false false 3 false true 12000000 12 false false 4 false true -7000000 -7 false false No definition available. No authoritative reference available. false 13 Total operating expenses 4 us-gaap_CostsAndExpenses us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 1933000000 1933 false false 2 false true 1838000000 1838 false false 3 false true 3982000000 3982 false false 4 false true 3539000000 3539 false false No definition available. No authoritative reference available. true 14 Operating income 3 us-gaap_OperatingIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 379000000 379 false false 2 false true 406000000 406 false false 3 false true 772000000 772 false false 4 false true 771000000 771 false false No definition available. No authoritative reference available. true 15 Other income (expense) 3 us-gaap_NonoperatingIncomeExpenseAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 16 Interest income 4 pgn_InterestAndDividendIncome pgn false credit duration monetary Includes all interest income, including impacts of discount accretion and premium amortization, and dividend income. false false false false false false false false false 1 false true 2000000 2 false false 2 false true 5000000 5 false false 3 false true 6000000 6 false false 4 false true 12000000 12 false false Includes all interest income, including impacts of discount accretion and premium amortization, and dividend income. No authoritative reference available. false 17 Allowance for equity funds used during construction 4 us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 36000000 36 false false 2 false true 27000000 27 false false 3 false true 75000000 75 false false 4 false true 50000000 50 false false No definition available. No authoritative reference available. false 18 Other, net 4 us-gaap_OtherNonoperatingIncomeExpense us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 13000000 13 false false 2 false true 3000000 3 false false 3 false true 12000000 12 false false 4 false true -2000000 -2 false false No definition available. No authoritative reference available. false 19 Total other income, net 4 us-gaap_NonoperatingIncomeExpense us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 51000000 51 false false 2 false true 35000000 35 false false 3 false true 93000000 93 false false 4 false true 60000000 60 false false No definition available. No authoritative reference available. true 20 Interest charges 3 us-gaap_InterestAndDebtExpenseAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 21 Interest charges 4 us-gaap_InterestExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 181000000 181 false false 2 false true 154000000 154 false false 3 false true 360000000 360 false false 4 false true 315000000 315 false false No definition available. No authoritative reference available. false 22 Allowance for borrowed funds used during construction 4 us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -12000000 -12 false false 2 false true -8000000 -8 false false 3 false true -24000000 -24 false false 4 false true -16000000 -16 false false No definition available. No authoritative reference available. false 23 Total interest charges, net 4 us-gaap_InterestAndDebtExpense us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 169000000 169 false false 2 false true 146000000 146 false false 3 false true 336000000 336 false false 4 false true 299000000 299 false false No definition available. No authoritative reference available. false 24 Income from continuing operations before income tax 3 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 261000000 261 false false 2 false true 295000000 295 false false 3 false true 529000000 529 false false 4 false true 532000000 532 false false No definition available. No authoritative reference available. false 25 Income tax expense 3 us-gaap_IncomeTaxExpenseBenefit us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 86000000 86 false false 2 false true 95000000 95 false false 3 false true 171000000 171 false false 4 false true 179000000 179 false false No definition available. No authoritative reference available. false 26 Income from continuing operations 3 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 175000000 175 false false 2 false true 200000000 200 false false 3 false true 358000000 358 false false 4 false true 353000000 353 false false No definition available. No authoritative reference available. true 27 Discontinued operations, net of tax 3 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -1000000 -1 false false 2 false true 5000000 5 false false 3 false true -1000000 -1 false false 4 false true 66000000 66 false false No definition available. No authoritative reference available. false 28 Net income 3 us-gaap_ProfitLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 174000000 174 false false 2 false true 205000000 205 false false 3 false true 357000000 357 false false 4 false true 419000000 419 false false No definition available. No authoritative reference available. false 29 Net income attributable to noncontrolling interests, net of tax 3 us-gaap_NetIncomeLossAttributableToNoncontrollingInterest us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true 0 0 false false 2 false true 0 0 false false 3 false true -1000000 -1 false false 4 false true -5000000 -5 false false No definition available. No authoritative reference available. false 30 Net income attributable to controlling interests 3 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 174000000 174 false false 2 false true 205000000 205 false false 3 false true 356000000 356 false false 4 false true 414000000 414 false false No definition available. No authoritative reference available. false 31 Average common shares outstanding - basic 3 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 280 280.00 false false 2 false true 261 261.00 false false 3 false true 278 278.00 false false 4 false true 261 261.00 false false No definition available. No authoritative reference available. false 33 Earnings Per Share Basic, [Abstract] 4 us-gaap_EarningsPerShareBasicAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 34 Income from continuing operations attributable to controlling interests, net of tax 5 us-gaap_IncomeLossFromContinuingOperationsPerBasicShare us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.62 0.62 false false 2 true true 0.76 0.76 false false 3 true true 1.28 1.28 false false 4 true true 1.34 1.34 false false No definition available. No authoritative reference available. false 35 Discontinued operations attributable to controlling interests, net of tax 5 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0 0 false false 2 true true 0.02 0.02 false false 3 true true 0 0 false false 4 true true 0.25 0.25 false false No definition available. No authoritative reference available. false 36 Net income attributable to controlling interests 5 us-gaap_EarningsPerShareBasic us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.62 0.62 false false 2 true true 0.78 0.78 false false 3 true true 1.28 1.28 false false 4 true true 1.59 1.59 false false No definition available. No authoritative reference available. true 37 Earnings Per Share, Diluted [Abstract] 4 us-gaap_EarningsPerShareDilutedAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 38 Income from continuing operations attributable to controlling interests, net of tax 5 us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.62 0.62 false false 2 true true 0.76 0.76 false false 3 true true 1.28 1.28 false false 4 true true 1.34 1.34 false false No definition available. No authoritative reference available. false 39 Discontinued operations attributable to controlling interests, net of tax 5 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0 0 false false 2 true true 0.02 0.02 false false 3 true true 0 0 false false 4 true true 0.25 0.25 false false No definition available. No authoritative reference available. false 40 Net income attributable to controlling interests 5 us-gaap_EarningsPerShareDiluted us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.62 0.62 false false 2 true true 0.78 0.78 false false 3 true true 1.28 1.28 false false 4 true true 1.59 1.59 false false No definition available. No authoritative reference available. true 41 Dividends declared per common share 3 us-gaap_CommonStockDividendsPerShareDeclared us-gaap true na duration decimal No definition available. false false false false false false false false true 1 true true 0.620 0.620 false false 2 true true 0.615 0.615 false false 3 true true 1.240 1.240 false false 4 true true 1.230 1.230 false false No definition available. No authoritative reference available. false 42 Amounts attributable to controlling interests 3 us-gaap_IncomeAmountsAttributableToReportingEntityDisclosuresAbstract us-gaap true na duration string No definition available. false false false false false true false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false false 0 0 false false 4 false false 0 0 false false No definition available. false 43 Income from continuing operations attributable to controlling interests, net of tax 4 us-gaap_IncomeLossFromContinuingOperations us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 175000000 175 false false 2 false true 200000000 200 false false 3 false true 357000000 357 false false 4 false true 349000000 349 false false No definition available. No authoritative reference available. false 44 Discontinued operations attributable to controlling interests, net of tax 4 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true -1000000 -1 false false 2 false true 5000000 5 false false 3 false true -1000000 -1 false false 4 false true 65000000 65 false false No definition available. No authoritative reference available. false 45 Net income attributable to controlling interests 4 us-gaap_NetIncomeLoss us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 true true 174000000 174 false false 2 true true 205000000 205 false false 3 true true 356000000 356 false false 4 true true 414000000 414 false false No definition available. No authoritative reference available. false false 4 40 false Millions NoRounding NoRounding false true