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purpose.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalse6falsefalsefalse00falsefalsefalsetruefalse7falsefalsefalse00falsefalsefalsetruefalse8falsefalsefalse00falsefalsefalsetruefalse9falsefalsefalse00falsefalsefalsetruefalse10falsefalsefalse00falsefalsefalsetruefalse11falsefalsefalse00falsefalsefalsetruefalse12falsefalsefalse00falsefalsefalsetruefalse13falsefalsefalse00falsefalsefalsetruefalse14truefalsefalse20000002falsetruefalsetruefalse15truefalsefalse20000002falsetruefalsetruefalse16truefalsefalse20000002falsetruefalsetruefalse17falsefalsefalse00falsefalsefalsetruefalse18truefalsefalse30000003falsetruefalsetruefalse19truefalsefalse30000003falsetruefalsetruefalse20truefalsefalse30000003falsetruefalsetruefalseMonetaryxbrli:monetaryItemTypemonetaryAmount expensed for ratemaking purpose.No authoritative reference available.falsefalseAmount expensed for ratemaking purpose209Summary of Significant Accounting Policies (Details 3) (USD $)MillionsUnKnownUnKnownUnKnowntruetrue