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true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string No definition available. false 6 Energy-related derivatives 4 us-gaap_FairValueAssetsMeasuredOnRecurringBasisDerivativeFinancialInstrumentsAssets us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 true true false false 7000000 7 false false false 2 true true false false 7000000 7 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 true true false false 7000000 7 true false false 77 true true false false 0 0 true false false 78 true true false false 7000000 7 true false false 79 true true false false 0 0 true false false 80 true true false false 0 0 true false false 81 true true false false 7000000 7 true false false 82 true true false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph a false 7 Interest rate derivatives 4 us-gaap_InterestRateDerivativeAssetsAtFairValue us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 8000000 8 false false false 2 false true false false 8000000 8 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 0 0 true false false 81 false true false false 8000000 8 true false false 82 false true false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 false 8 Nuclear decommissioning trusts 4 us-gaap_DecommissioningTrustAssetsAmount us-gaap true debit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 1061000000 1061 [1],[2] false false false 2 false true false false 1061000000 1061 [1],[2] false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false true false false 272000000 272 [1] true false false 9 false true false false 17000000 17 [1] true false false 10 false true false false 0 0 [1] true false false 11 false true false false 0 0 [1] true false false 12 false true false false 0 0 [1] true false false 13 false false false false 0 0 true false false 14 false true false false 50000000 50 [1] true false false 15 false true false false 7000000 7 [1] true false false 16 false true false false 80000000 80 [1] true false false 17 false true false false 36000000 36 [1] true false false 18 false true false false 12000000 12 [1] true false false 19 false false false false 0 0 true false false 20 false true false false 0 0 [1] true false false 21 false true false false 0 0 [1] true false false 22 false true false false 0 0 [1] true false false 23 false true false false 0 0 [1] true false false 24 false true false false 0 0 [1] true false false 25 false true false false 322000000 322 [1] true false false 26 false true false false 24000000 24 [1] true false false 27 false true false false 80000000 80 [1] true false false 28 false true false false 36000000 36 [1] true false false 29 false true false false 12000000 12 [1] true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false true false false 388000000 388 [1] true false false 37 false true false false 0 0 [1] true false false 38 false true false false 0 0 [1] true false false 39 false true false false 0 0 [1] true false false 40 false true false false 0 0 [1] true false false 41 false true false false 0 0 [1] true false false 42 false false false false 0 0 true false false 43 false true false false 1000000 1 [1] true false false 44 false true false false 24000000 24 [1] true false false 45 false true false false 37000000 37 [1] true false false 46 false true false false 78000000 78 [1] true false false 47 false true false false 41000000 41 [1] true false false 48 false true false false 18000000 18 [1] true false false 49 false false false false 0 0 true false false 50 false true false false 0 0 [1] true false false 51 false true false false 0 0 [1] true false false 52 false true false false 0 0 [1] true false false 53 false true false false 0 0 [1] true false false 54 false true false false 0 0 [1] true false false 55 false true false false 0 0 [1] true false false 56 false true false false 389000000 389 [1] true false false 57 false true false false 24000000 24 [1] true false false 58 false true false false 37000000 37 [1] true false false 59 false true false false 78000000 78 [1] true false false 60 false true false false 41000000 41 [1] true false false 61 false true false false 18000000 18 [1] true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 677000000 677 [1],[2] true false false 81 false true false false 384000000 384 [1],[2] true false false 82 false true false false 0 0 [1],[2] true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Discloses the fair value amount of decommissioning trust assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 143 -Paragraph 22 -Subparagraph b false 9 Cash equivalents and restricted cash 4 us-gaap_FairValueAssetsMeasuredOnRecurringBasisCashAndCashEquivalents us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 142000000 142 false false false 2 false true false false 142000000 142 false false false 3 false true false false 32000000 32 true false false 4 false true false false 32000000 32 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false true false false 32000000 32 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false true false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false true false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false true false false 52000000 52 true false false 31 false true false false 52000000 52 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false true false false 52000000 52 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false true false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false true false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false true false false 12000000 12 true false false 63 false false false false 0 0 true false false 64 false true false false 12000000 12 true false false 65 false true false false 0 0 true false false 66 false true false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 142000000 142 true false false 81 false true false false 0 0 true false false 82 false true false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents a certain statement of financial position asset caption which represents a class of assets, or which may include an individual asset, measured at fair value on a recurring basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph a true 10 Other 4 us-gaap_OtherAssetsFairValueDisclosure us-gaap true debit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 91000000 91 false false false 2 false true false false 91000000 91 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 24000000 24 true false false 81 false true false false 48000000 48 true false false 82 false true false false 19000000 19 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This element represents the fair value of assets categorized as other which are not in and of themselves material enough to require separate disclosure. No authoritative reference available. true 11 Fair value assets, total 4 so_FairValueAssetsMeasuredOnRecurringBasisTotal so false debit instant Fair Value Assets Measured On Recurring Basis Total false false false false false false false false false false false totallabel false 1 false true false false 1309000000 1309 false false false 2 false true false false 1309000000 1309 false false false 3 false true false false 506000000 506 true false false 4 false true false false 506000000 506 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false true false false 321000000 321 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false true false false 185000000 185 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false true false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false true false false 639000000 639 true false false 31 false true false false 639000000 639 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false true false false 440000000 440 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false true false false 199000000 199 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false true false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 843000000 843 true false false 81 false true false false 447000000 447 true false false 82 false true false false 19000000 19 true false false 83 false true false false 19000000 19 true false false 84 false true false false 35000000 35 true false false xbrli:monetaryItemType monetary Fair Value Assets Measured On Recurring Basis Total No authoritative reference available. true 12 Energy-related derivatives 4 us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisDerivativeFinancialInstrumentsLiabilities us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 209000000 209 false false false 2 false true false false 209000000 209 false false false 3 false true false false 45000000 45 true false false 4 false true false false 45000000 45 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false true false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false true false false 45000000 45 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false true false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false true false false 93000000 93 true false false 31 false true false false 93000000 93 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false true false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false true false false 93000000 93 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false true false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false true false false 15000000 15 true false false 63 false false false false 0 0 true false false 64 false true false false 0 0 true false false 65 false true false false 15000000 15 true false false 66 false true false false 0 0 true false false 67 false true false false 48000000 48 true false false 68 false true false false 0 0 true false false 69 false true false false 48000000 48 true false false 70 false true false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false true false false 8000000 8 true false false 77 false true false false 0 0 true false false 78 false true false false 8000000 8 true false false 79 false true false false 0 0 true false false 80 false true false false 0 0 true false false 81 false true false false 209000000 209 true false false 82 false true false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents a certain statement of financial position liability caption which represents a class of liabilities, or which may include an individual liability, measured at fair value on a recurring basis. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph a false 13 Interest rate derivatives 4 us-gaap_InterestRateDerivativeLiabilitiesAtFairValue us-gaap true credit instant No definition available. false false false false false false false false false false false totallabel false 1 false true false false 1000000 1 false false false 2 false true false false 1000000 1 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 0 0 true false false 81 false true false false 1000000 1 true false false 82 false true false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 true 14 Fair value liabilities, total 4 so_FairValueLiabilitiesMeasuredOnRecurringBasisLiabilitiesTotal so false credit instant Fair Value Liabilities Measured On Recurring Basis Liabilities total. false false false false false false false false false false false totallabel false 1 false true false false 210000000 210 false false false 2 false true false false 210000000 210 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 0 0 true false false 81 false true false false 210000000 210 true false false 82 false true false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair Value Liabilities Measured On Recurring Basis Liabilities total. No authoritative reference available. true 15 Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments 3 so_FairValueMeasurementsOfInvestmentsCalculatedAtNetAssetValuePerShareAsWellAsNatureAndRiskOfThoseInvestmentsAbstract so false na duration Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those... false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Fair value measurements of investments calculated at net asset value per share as well as the nature and risk of those investments. false 16 Fair Value 4 so_FairValueOfInvestmentsCalculatedAtNetAssetValue so false na instant Fair value of investments calculated at net asset value. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false true false false 76000000 76 true false false 6 false true false false 32000000 32 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false true false false 38000000 38 true false false 33 false true false false 18000000 18 true false false 34 false true false false 52000000 52 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false true false false 12000000 12 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false true false false 38000000 38 true false false 72 false true false false 18000000 18 true false false 73 false true false false 76000000 76 true false false 74 false true false false 142000000 142 true false false 75 false true false false 3000000 3 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair value of investments calculated at net asset value. No authoritative reference available. false 17 Unfunded Commitments 4 so_UnfundedCommitments so false na instant Unfunded Commitments. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 None None true false false 6 false false false false 0 0 None None true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 None None true false false 33 false false false false 0 0 None None true false false 34 false false false false 0 0 None None true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 None None true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 None None true false false 72 false false false false 0 0 None None true false false 73 false false false false 0 0 None None true false false 74 false false false false 0 0 None None true false false 75 false false false false 0 0 None None true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Unfunded Commitments. No authoritative reference available. false 18 Redemption Frequency 4 so_RedemptionFrequency so false na instant Redemption Frequency. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 Daily Daily true false false 6 false false false false 0 0 Daily Daily true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 Daily Daily true false false 33 false false false false 0 0 Daily Daily true false false 34 false false false false 0 0 Daily Daily true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 Daily Daily true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 Daily Daily true false false 72 false false false false 0 0 Daily Daily true false false 73 false false false false 0 0 Daily Daily true false false 74 false false false false 0 0 Daily Daily true false false 75 false false false false 0 0 Daily Daily true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Redemption Frequency. No authoritative reference available. false 19 Redemption Notice Period 4 so_RedemptionNoticePeriod so false na instant Redemption Notice Period. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 15 days 15 days true false false 6 false false false false 0 0 Not applicable Not applicable true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 1 to 3 days 1 to 3 days true false false 33 false false false false 0 0 Not applicable Not applicable true false false 34 false false false false 0 0 Not applicable Not applicable true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 Not applicable Not applicable true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 1 to 3 days 1 to 3 days true false false 72 false false false false 0 0 Not applicable Not applicable true false false 73 false false false false 0 0 15 days 15 days true false false 74 false false false false 0 0 Not applicable Not applicable true false false 75 false false false false 0 0 Not applicable Not applicable true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Redemption Notice Period. No authoritative reference available. false 20 Changes in the fair value measurement of the Level 3 items 3 so_ChangesInFairValueMeasurementOfLevel3ItemsAbstract so false na duration Changes in the fair value measurement of the Level 3 items. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Changes in the fair value measurement of the Level 3 items. false 21 Beginning balance 4 so_FairValueAssetsMeasuredOnRecurringBasisTotal so false debit instant Fair Value Assets Measured On Recurring Basis Total false false false false false false false false true false false periodstartlabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false true false false 321000000 321 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false true false false 185000000 185 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false true false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false true false false 440000000 440 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false true false false 199000000 199 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false true false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 843000000 843 true false false 81 false true false false 447000000 447 true false false 82 false true false false 19000000 19 true false false 83 false true false false 19000000 19 true false false 84 false true false false 35000000 35 true false false xbrli:monetaryItemType monetary Fair Value Assets Measured On Recurring Basis Total No authoritative reference available. false 22 Total gains (losses)- realized/unrealized: 4 so_TotalGainsLossesRealizedUnrealizedAbstract so false na duration Total gains losses realized unrealized Abstract. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Total gains losses realized unrealized Abstract. false 23 Included in OCI 5 so_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetOrLiabilitiesGainLossInOtherIncludedInOtherComprehensiveIncome so false debit duration Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liabilities Gain Loss In Other... false false false false false false false false false false false totallabel false 1 false true false false 0 0 false false false 2 false true false false 4000000 4 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Or Liabilities Gain Loss In Other Included In Other Comprehensive Income. No authoritative reference available. true 24 Transfers out of Level 3 5 us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersNet us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 0 0 false false false 2 false true false false -20000000 -20 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(3) true 25 Ending balance 4 so_FairValueAssetsMeasuredOnRecurringBasisTotal so false debit instant Fair Value Assets Measured On Recurring Basis Total false false false false false false false false false true false periodendlabel false 1 false true false false 1309000000 1309 false false false 2 false true false false 1309000000 1309 false false false 3 false true false false 506000000 506 true false false 4 false true false false 506000000 506 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false true false false 321000000 321 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false true false false 185000000 185 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false true false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false true false false 639000000 639 true false false 31 false true false false 639000000 639 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false true false false 440000000 440 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false true false false 199000000 199 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false true false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false true false false 843000000 843 true false false 81 false true false false 447000000 447 true false false 82 false true false false 19000000 19 true false false 83 false true false false 19000000 19 true false false 84 false true false false 35000000 35 true false false xbrli:monetaryItemType monetary Fair Value Assets Measured On Recurring Basis Total No authoritative reference available. false 27 Long-term debt: 4 us-gaap_LongTermDebtAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string No definition available. false 28 Long-term debt, Carrying Amount 5 us-gaap_DebtInstrumentCarryingAmount us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 19548000000 19548 false false false 2 false true false false 19548000000 19548 false false false 3 false true false false 6183000000 6183 true false false 4 false true false false 6183000000 6183 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false true false false 8315000000 8315 true false false 31 false true false false 8315000000 8315 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false true false false 1174000000 1174 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false true false false 491000000 491 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false true false false 1298000000 1298 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number APB14-1 -Paragraph 31 -Subparagraph b Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 false 29 Long-term debt, Fair Value 5 us-gaap_DebtInstrumentFairValue us-gaap true credit instant No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 20641000000 20641 false false false 2 false true false false 20641000000 20641 false false false 3 false true false false 6607000000 6607 true false false 4 false true false false 6607000000 6607 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false true false false 8719000000 8719 true false false 31 false true false false 8719000000 8719 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false true false false 1232000000 1232 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false true false false 521000000 521 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false true false false 1417000000 1417 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Estimated fair value of the debt instrument at the balance-sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 false 30 Fair Value Measurements (Textuals) [Abstract] 3 so_FairValueMeasurementsTextualsAbstract so false na duration Fair Value Measurements Textuals Abstract. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Fair Value Measurements Textuals Abstract. false 31 Maximum number of months related to maturities in the portfolio not to exceeded from the date of purchase 4 so_MaximumNumberOfMonthsRelatedToMaturitiesInPortfolioNotToExceededFromDateOfPurchase so false na duration Maximum number of months related to maturities in the portfolio not to exceeded from the date of purchase. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 13 13 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Maximum number of months related to maturities in the portfolio not to exceeded from the date of purchase. No authoritative reference available. false 32 Maximum number of days related to dollar-weighted average portfolio maturities regarding commingled funds 4 so_MaximumNumberOfDaysRelatedToDollarWeightedAveragePortfolioMaturitiesRegardingCommingledFunds so false na duration Maximum number of days related to dollar weighted average portfolio maturities regarding commingled funds. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 90 90 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Maximum number of days related to dollar weighted average portfolio maturities regarding commingled funds. No authoritative reference available. false 33 Minimum number of months related to the reset date of maturities in the portfolio with put features or floating rates 4 so_MinimumNumberOfMonthsRelatedToResetDateOfMaturitiesInPortfolioWithPutFeaturesOrFloatingRates so false na duration Minimum number of months related to the reset date of maturities in the portfolio with put features or floating rates. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 13 13 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Minimum number of months related to the reset date of maturities in the portfolio with put features or floating rates. No authoritative reference available. false 34 Maximum maturity for longer term investment grade fixed income obligations (in years) 4 so_MaximumMaturityForLongerTermInvestmentGradeFixedIncomeObligations so false na duration Maximum maturity for longer term investment grade fixed income obligations. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 5 5 false false false 3 false false false false 0 0 true false false 4 false false false false 0 0 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 false false false false 0 0 true false false 31 false false false false 0 0 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:stringItemType string Maximum maturity for longer term investment grade fixed income obligations. No authoritative reference available. false 35 Decrease in fair value of the funds, including reinvested interest and dividends 4 so_DecreaseInFairValueOfFundsIncludingReinvestedInterestAndDividends so false credit duration Decrease in fair value of the funds, including reinvested interest and dividends. false false false false false false false false false false false verboselabel false 1 true true false false 86000000 86 false false false 2 true true false false 42000000 42 false false false 3 true true false false 36000000 36 true false false 4 true true false false 16000000 16 true false false 5 false false false false 0 0 true false false 6 false false false false 0 0 true false false 7 false false false false 0 0 true false false 8 false false false false 0 0 true false false 9 false false false false 0 0 true false false 10 false false false false 0 0 true false false 11 false false false false 0 0 true false false 12 false false false false 0 0 true false false 13 false false false false 0 0 true false false 14 false false false false 0 0 true false false 15 false false false false 0 0 true false false 16 false false false false 0 0 true false false 17 false false false false 0 0 true false false 18 false false false false 0 0 true false false 19 false false false false 0 0 true false false 20 false false false false 0 0 true false false 21 false false false false 0 0 true false false 22 false false false false 0 0 true false false 23 false false false false 0 0 true false false 24 false false false false 0 0 true false false 25 false false false false 0 0 true false false 26 false false false false 0 0 true false false 27 false false false false 0 0 true false false 28 false false false false 0 0 true false false 29 false false false false 0 0 true false false 30 true true false false 50000000 50 true false false 31 true true false false 26000000 26 true false false 32 false false false false 0 0 true false false 33 false false false false 0 0 true false false 34 false false false false 0 0 true false false 35 false false false false 0 0 true false false 36 false false false false 0 0 true false false 37 false false false false 0 0 true false false 38 false false false false 0 0 true false false 39 false false false false 0 0 true false false 40 false false false false 0 0 true false false 41 false false false false 0 0 true false false 42 false false false false 0 0 true false false 43 false false false false 0 0 true false false 44 false false false false 0 0 true false false 45 false false false false 0 0 true false false 46 false false false false 0 0 true false false 47 false false false false 0 0 true false false 48 false false false false 0 0 true false false 49 false false false false 0 0 true false false 50 false false false false 0 0 true false false 51 false false false false 0 0 true false false 52 false false false false 0 0 true false false 53 false false false false 0 0 true false false 54 false false false false 0 0 true false false 55 false false false false 0 0 true false false 56 false false false false 0 0 true false false 57 false false false false 0 0 true false false 58 false false false false 0 0 true false false 59 false false false false 0 0 true false false 60 false false false false 0 0 true false false 61 false false false false 0 0 true false false 62 false false false false 0 0 true false false 63 false false false false 0 0 true false false 64 false false false false 0 0 true false false 65 false false false false 0 0 true false false 66 false false false false 0 0 true false false 67 false false false false 0 0 true false false 68 false false false false 0 0 true false false 69 false false false false 0 0 true false false 70 false false false false 0 0 true false false 71 false false false false 0 0 true false false 72 false false false false 0 0 true false false 73 false false false false 0 0 true false false 74 false false false false 0 0 true false false 75 false false false false 0 0 true false false 76 false false false false 0 0 true false false 77 false false false false 0 0 true false false 78 false false false false 0 0 true false false 79 false false false false 0 0 true false false 80 false false false false 0 0 true false false 81 false false false false 0 0 true false false 82 false false false false 0 0 true false false 83 false false false false 0 0 true false false 84 false false false false 0 0 true false false xbrli:monetaryItemType monetary Decrease in fair value of the funds, including reinvested interest and dividends. No authoritative reference available. false 1 Excludes receivables related to investment income, pending investment sales, and payables related to pending investment purchases. 2 For additional detail, see the nuclear decommissioning trusts sections for Alabama Power and Georgia Power in this table. 84 30 false Millions UnKnown UnKnown false true