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Basis of Presentation (Details) shares in Millions, $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 USD ($) mi² retail_customers shares | Mar. 31, 2015 USD ($) | Dec. 31, 2015 USD ($)
Basis of Presentation [Abstract] |  |  |
Regulatory deferral of settled derivative instruments |  | $ 2 |
Service Area Sq Miles | mi² | 4,000 |  |
Incorporated Cities | 52 |  |
Number of Retail Customers | retail_customers | 855,573 |  |
Service Area Population | shares | 1.8 |  |
Percent of State's Population | 46.00% |  |
Other Comprehensive Income | $ 0 | 0 |
Unamortized Debt Issuance Expense | $ 12 |  | $ 11
Decoupling Mechanism Deferrals, Net |  | (3) |
Cash received pursuant to the Residential Exchange Program |  | $ 1 |

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- Definition The deferral, which can be either a positive or negaitive amount depending on whether a collection from or refund to customers results, of the amounts recorded in net income for energy useage by customers on a weather adjusted basis that is different from base rates as determined under the Company's decoupling mechanism, expected to be recovered or refunded in future periods. + References No definition available. + Details
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- Definition Number of incorporated cities in service area. + References No definition available. + Details
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- Definition Includes residential, commercial and industrial. + References No definition available. + Details
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- Definition Service area population as a percent of the state's population. + References No definition available. + Details
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- Definition Service Area Population + References No definition available. + Details
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- Definition Approximate square miles of service area. + References No definition available. + Details
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- Definition Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
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- Definition The increase (decrease) during the reporting period in the amount of (a) prepayments by customers for goods or services to be provided at a later date, (b) the amount of customer money held in customer accounts, including security deposits, collateral for a current or future transactions, initial payment of the cost of acquisition or for the right to enter into a contract or agreement, or (c) a combination of (a) and (b). + References No definition available. + Details
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- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4569616-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4569643-111683 + Details
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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