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Asset Retirement Obligations | 9 Months Ended
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Sep. 30, 2014
Asset Retirement Obligations [Abstract] |
Asset Retirement Obligations | ASSET RETIREMENT OBLIGATIONS ASH BASINS As a result of the Coal Ash Act and the agreement with SCDHEC discussed in Note 5, Duke Energy Carolinas and Duke Energy Progress recorded asset retirement obligations (ARO) at September 30, 2014 of $2,026 million and $1,406 million, respectively, related to closure of ash basins in North Carolina and South Carolina. The amounts recorded assume ash will retain a non-hazardous designation by the EPA. The ARO amount is based upon estimated ash basin closure costs for each of Duke Energy's 32 ash basins located at 14 plants in North Carolina and an ash basin at a plant in South Carolina. The amount recorded represents the discounted cash flows for estimated closure costs of these ash basins based upon probability weightings of the potential closure methods as evaluated on a site by site basis. Actual costs to be incurred will be dependent upon factors that vary from site to site. The most significant factors are the method and timeframe of closure at the individual sites. Closure methods considered include removing the water from the basins and capping the ash with a synthetic barrier, excavating and relocating the ash to a lined structural fill or lined landfill, or recycling the ash for concrete or some other beneficial use. The ultimate method and timetable for closure will be in compliance with future standards set by the Coal Ash Management Commission established by the Coal Ash Act. The ARO amount will be adjusted as additional information is gained from the Coal Ash Management Commission on acceptable compliance approaches which may change management assumptions. Asset retirement costs associated with the asset retirement obligations for operating plants and retired plants have been included in Net property, plant and equipment, and Regulatory assets, respectively, on the Condensed Consolidated Balance Sheets. As of September 30, 2014, $1,559 million and $610 million were recorded in Net property, plant and equipment for Duke Energy Carolinas and Duke Energy Progress, respectively, and $467 million and $763 million were recorded in Regulatory assets for Duke Energy Carolinas and Duke Energy Progress, respectively. The asset retirement costs recorded for Duke Energy Progress are net of $33 million of Regulatory liabilities related to cost of removal. Cost recovery for these expenditures is believed to be probable and will be pursued through the normal ratemaking process with the NCUC, PSCSC, and FERC. The following table presents changes in the liability associated with asset retirement obligations for Duke Energy and the Subsidiary Registrants impacted by the Coal Ash Act and the agreement with SCDHEC.
(in millions) | Duke Energy |  |  | Duke Energy Carolinas |  |  | Progress Energy |  |  | Duke Energy Progress |
Balance at December 31, 2013(a)(b) | $ | 4,958 |  |  | $ | 1,594 |  |  | $ | 2,570 |  |  | $ | 1,737 |
Accretion expense(c) | 164 |  |  | 71 |  |  | 91 |  |  | 63 |
Liabilities settled | (56 | ) |  | — |  |  | (52 | ) |  | — |
Liabilities incurred in the current year(d) | 3,433 |  |  | 2,026 |  |  | 1,406 |  |  | 1,406 |
Balance at September 30, 2014 | $ | 8,499 |  |  | $ | 3,691 |  |  | $ | 4,015 |  |  | $ | 3,206 |
(a) | The balance as of December 31, 2013 primarily relates to decommissioning nuclear power facilities, asbestos removal and closure of landfills at fossil generation facilities.
(b) | The balance at December 31, 2013 includes $8 million reported in Other current liabilities on the Condensed Consolidated Balance Sheets at Duke Energy, Progress Energy and Duke Energy Progress.
(c) | Substantially all accretion expense for the nine months ended September 30, 2014 relates to Duke Energy's regulated electric operations from previously established asset retirement obligations and has been deferred in accordance with regulatory accounting treatment.
(d) | Amounts relate to asset obligations recorded in the third quarter of 2014 as a result of the Coal Ash Act and an agreement with the SCDHEC related to the W.S Lee Steam Station.

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- Definition The entire disclosure for an asset retirement obligation and the associated long-lived asset. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7569-110849 + Details
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