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Basis of Presentation (Details) shares in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2017 USD ($) mi² retail_customers shares | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) mi² retail_customers shares | Jun. 30, 2016 USD ($) | Dec. 31, 2016 USD ($)
Basis of Presentation [Abstract] |  |  |  |  |
Service Area Sq Miles | mi² | 4,000 |  | 4,000 |  |
Incorporated Cities | 51 |  | 51 |  |
Number of Retail Customers | retail_customers | 872,000 |  | 872,000 |  |
Service Area Population | shares | 1.9 |  | 1.9 |  |
Percent of State's Population | 46.00% |  | 46.00% |  |
Decoupling Mechanism Deferrals, Net |  |  | $ (15,000,000) | $ (3,000,000) |
Repayments of Long-term Capital Lease Obligations |  |  |  | 2,000,000 |
Payments of Debt Issuance Costs |  |  |  | 1,000,000 |
Other Comprehensive Income | $ 1,000,000 |  | 0 | 0 |
Other comprehensive loss | 1,000,000 | $ 0 | 0 | $ 0 |
Unamortized Debt Issuance Expense | $ 11,000,000 |  | $ 11,000,000 |  | $ 11,000,000

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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 Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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