v2.4.0.8

Asset Retirement Obligations (Tables) | 9 Months Ended
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Sep. 30, 2014
Asset Retirement Obligations [Abstract] |
Schedule of Change in Asset Retirement Obligation | 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 Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859 + Details
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