1.0.0.3 true CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) In Millions 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 3 Beginning Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 true true 8693000000 8693 false false 2 true true 8479000000 8479 false false 3 true true 8269000000 8269 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 4 Net Income 2 pgn_Netincomelossincludingportionattributabletononcontrollinginterestequitystatement pgn false credit duration monetary The consolidated profit or loss for the period as presented on the statement of changes in total equity, net of income taxes,... false false false false false false false false false 1 false true 757000000 757 [1] false false 2 false true 836000000 836 false false 3 false true 496000000 496 false false 4 false false 0 0 false false The consolidated profit or loss for the period as presented on the statement of changes in total equity, net of income taxes, including the portion attributable to the noncontrolling interest. No authoritative reference available. false 5 Other comprehensive income (loss) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true 29000000 29 false false 2 false true -82000000 -82 false false 3 false true 15000000 15 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 6 Adjustment to initially apply FASB Interpretation No. 48 2 us-gaap_CumulativeEffectOfInitialAdoptionOfFIN48 us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true -2000000 -2 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 7 Issuance of shares 2 us-gaap_StockIssuedDuringPeriodValueNewIssues us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 623000000 623 false false 2 false true 131000000 131 false false 3 false true 46000000 46 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 9 Stock options exercised 2 us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false true 1000000 1 false false 3 false true 105000000 105 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 10 Allocation of ESOP Shares 2 pgn_AllocationOfEsopShares pgn false credit duration monetary Value of shares released from ESOP suspense account and allocated to participant accounts. false false false false false false false false false 1 false true 21000000 21 false false 2 false true 25000000 25 false false 3 false true 28000000 28 false false 4 false false 0 0 false false Value of shares released from ESOP suspense account and allocated to participant accounts. No authoritative reference available. false 11 Stock-based compensation expense 2 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation 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 33000000 33 false false 3 false true 71000000 71 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 12 Dividends ($2.480, $2.465 and $2.445 per share for 2009, 2008 and 2007, respectively) 2 us-gaap_Dividends us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -704000000 -704 false false 2 false true -646000000 -646 false false 3 false true -631000000 -631 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 13 Sale of subsidiary shares to noncontrolling interests 2 us-gaap_MinorityInterestIncreaseFromStockIssuance us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true 37000000 37 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 14 Distributions to noncontrolling interests 2 us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -1000000 -1 false false 2 false true -85000000 -85 false false 3 false true -10000000 -10 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 15 Contributions from noncontrolling interests 2 pgn_NoncontrollingInterestsIncreaseFromContributionsForNoncontrollingInterestHolders pgn false credit duration monetary Increase in noncontrolling interest balance from contributions from noncontrolling interest holders. false false false false false false false false false 1 false false 0 0 false false 2 false true 2000000 2 false false 3 false true 52000000 52 false false 4 false false 0 0 false false Increase in noncontrolling interest balance from contributions from noncontrolling interest holders. No authoritative reference available. false 16 Other transactions 2 pgn_NoncontrollingInterestsOtherTransactions pgn false credit duration monetary Change in noncontrolling interest balance not separately disclosed in the statement of stockholders' equity. false false false false false false false false false 1 false true 1000000 1 false false 2 false true -1000000 -1 false false 3 false true 3000000 3 false false 4 false false 0 0 false false Change in noncontrolling interest balance not separately disclosed in the statement of stockholders' equity. No authoritative reference available. false 18 Ending Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true 9455000000 9455 false false 2 false true 8693000000 8693 false false 3 false true 8479000000 8479 false false 4 false true 8269000000 8269 false false No definition available. No authoritative reference available. false 19 Common Stock [Member] 0 na true na na na No definition available. false true false false false false 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. No authoritative reference available. false 20 Beginning Balance, shares 2 us-gaap_SharesIssued us-gaap true na instant shares No definition available. false false false false false false true false false 1 false true 264000000 264 false false 2 false true 260000000 260 false false 3 false true 256000000 256 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 21 Beginning Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 6206000000 6206 false false 2 false true 6028000000 6028 false false 3 false true 5791000000 5791 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 25 Issuance of shares 2 us-gaap_StockIssuedDuringPeriodValueNewIssues us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false true 623000000 623 false false 2 false true 131000000 131 false false 3 false true 46000000 46 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 26 Issuance of shares, shares 2 us-gaap_StockIssuedDuringPeriodSharesNewIssues us-gaap true na duration shares No definition available. false false false false false false false false false 1 false true 17000000 17 false false 2 false true 4000000 4 false false 3 false true 4000000 4 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 27 Stock options exercised 2 us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false true 1000000 1 false false 3 false true 105000000 105 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 28 Allocation of ESOP Shares 2 pgn_AllocationOfEsopShares pgn false credit duration monetary Value of shares released from ESOP suspense account and allocated to participant accounts. false false false false false false false false false 1 false true 8000000 8 false false 2 false true 13000000 13 false false 3 false true 15000000 15 false false 4 false false 0 0 false false Value of shares released from ESOP suspense account and allocated to participant accounts. No authoritative reference available. false 29 Stock-based compensation expense 2 us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation 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 33000000 33 false false 3 false true 71000000 71 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 35 Ending Balance, shares 2 us-gaap_SharesIssued us-gaap true na instant shares No definition available. false false false false false false false true false 1 false true 281000000 281 false false 2 false true 264000000 264 false false 3 false true 260000000 260 false false 4 false true 256000000 256 false false No definition available. No authoritative reference available. false 36 Ending Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true 6873000000 6873 false false 2 false true 6206000000 6206 false false 3 false true 6028000000 6028 false false 4 false true 5791000000 5791 false false No definition available. No authoritative reference available. false 37 Unearned Employee Stock Ownership Plan [Member] 0 na true na na na No definition available. false true false false false false 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. No authoritative reference available. false 39 Beginning Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true -25000000 -25 false false 2 false true -37000000 -37 false false 3 false true -50000000 -50 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 46 Allocation of ESOP Shares 2 pgn_AllocationOfEsopShares pgn false credit duration monetary Value of shares released from ESOP suspense account and allocated to participant accounts. false false false false false false false false false 1 false true 13000000 13 false false 2 false true 12000000 12 false false 3 false true 13000000 13 false false 4 false false 0 0 false false Value of shares released from ESOP suspense account and allocated to participant accounts. No authoritative reference available. false 54 Ending Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true -12000000 -12 false false 2 false true -25000000 -25 false false 3 false true -37000000 -37 false false 4 false true -50000000 -50 false false No definition available. No authoritative reference available. false 55 Accumulated Other Comprehensive Income [Member] 0 na true na na na No definition available. false true false false false false 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. No authoritative reference available. false 57 Beginning Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true -116000000 -116 false false 2 false true -34000000 -34 false false 3 false true -49000000 -49 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 59 Other comprehensive income (loss) 2 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration monetary No definition available. false false false false false false false false false 1 false true 29000000 29 false false 2 false true -82000000 -82 false false 3 false true 15000000 15 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 72 Ending Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true -87000000 -87 false false 2 false true -116000000 -116 false false 3 false true -34000000 -34 false false 4 false true -49000000 -49 false false No definition available. No authoritative reference available. false 73 Retained Earnings [Member] 0 na true na na na No definition available. false true false false false false 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. No authoritative reference available. false 75 Beginning Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 2622000000 2622 false false 2 false true 2438000000 2438 false false 3 false true 2567000000 2567 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 76 Net Income 2 pgn_Netincomelossincludingportionattributabletononcontrollinginterestequitystatement pgn false credit duration monetary The consolidated profit or loss for the period as presented on the statement of changes in total equity, net of income taxes,... false false false false false false false false false 1 false true 757000000 757 [1] false false 2 false true 830000000 830 false false 3 false true 504000000 504 false false 4 false false 0 0 false false The consolidated profit or loss for the period as presented on the statement of changes in total equity, net of income taxes, including the portion attributable to the noncontrolling interest. No authoritative reference available. false 78 Adjustment to initially apply FASB Interpretation No. 48 2 us-gaap_CumulativeEffectOfInitialAdoptionOfFIN48 us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true -2000000 -2 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 84 Dividends ($2.480, $2.465 and $2.445 per share for 2009, 2008 and 2007, respectively) 2 us-gaap_Dividends us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -704000000 -704 false false 2 false true -646000000 -646 false false 3 false true -631000000 -631 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 90 Ending Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 false true 2675000000 2675 false false 2 false true 2622000000 2622 false false 3 false true 2438000000 2438 false false 4 false true 2567000000 2567 false false No definition available. No authoritative reference available. false 91 Noncontrolling Interest [Member] 0 na true na na na No definition available. false true false false false false 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. No authoritative reference available. false 93 Beginning Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false true false false 1 false true 6000000 6 false false 2 false true 84000000 84 false false 3 false true 10000000 10 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 94 Net Income 2 pgn_Netincomelossincludingportionattributabletononcontrollinginterestequitystatement pgn false credit duration monetary The consolidated profit or loss for the period as presented on the statement of changes in total equity, net of income taxes,... false false false false false false false false false 1 false false 0 0 false false 2 false true 6000000 6 false false 3 false true -8000000 -8 false false 4 false false 0 0 false false The consolidated profit or loss for the period as presented on the statement of changes in total equity, net of income taxes, including the portion attributable to the noncontrolling interest. No authoritative reference available. false 103 Sale of subsidiary shares to noncontrolling interests 2 us-gaap_MinorityInterestIncreaseFromStockIssuance us-gaap true credit duration monetary No definition available. false false false false false false false false false 1 false false 0 0 false false 2 false false 0 0 false false 3 false true 37000000 37 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 104 Distributions to noncontrolling interests 2 us-gaap_MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders us-gaap true debit duration monetary No definition available. false false false false false false false false false 1 false true -1000000 -1 false false 2 false true -85000000 -85 false false 3 false true -10000000 -10 false false 4 false false 0 0 false false No definition available. No authoritative reference available. false 105 Contributions from noncontrolling interests 2 pgn_NoncontrollingInterestsIncreaseFromContributionsForNoncontrollingInterestHolders pgn false credit duration monetary Increase in noncontrolling interest balance from contributions from noncontrolling interest holders. false false false false false false false false false 1 false false 0 0 false false 2 false true 2000000 2 false false 3 false true 52000000 52 false false 4 false false 0 0 false false Increase in noncontrolling interest balance from contributions from noncontrolling interest holders. No authoritative reference available. false 106 Other transactions 2 pgn_NoncontrollingInterestsOtherTransactions pgn false credit duration monetary Change in noncontrolling interest balance not separately disclosed in the statement of stockholders' equity. false false false false false false false false false 1 false true 1000000 1 false false 2 false true -1000000 -1 false false 3 false true 3000000 3 false false 4 false false 0 0 false false Change in noncontrolling interest balance not separately disclosed in the statement of stockholders' equity. No authoritative reference available. false 108 Ending Balance 2 us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit instant monetary No definition available. false false false false false false false true false 1 true true 6000000 6 false false 2 true true 6000000 6 false false 3 true true 84000000 84 false false 4 true true 10000000 10 false false No definition available. No authoritative reference available. false 1 Consolidated net income of $761 million includes $4 million attributable to preferred shareholders of subsidiaries, which is not a component of total equity and is excluded from the table above. false 4 46 false Millions Millions UnKnown false true