v2.4.0.6

Commitments and Contingencies (Table) | 3 Months Ended
--- | ---
Mar. 31, 2013 | Mar. 31, 2012
Valuation and Qualifying Accounts Disclosure [Line Items] |  |
Accrual For Environmental Loss Contingencies [Table Text Block] |
Balance at December 31, 2012 |  | $ | 75 |  | $ | 12 |  | $ | 33 |  | $ | 14 |  | $ | 19 |  | $ | 15 |  | $ | 8
Provisions / adjustments |  |  | 2 |  |  | ― |  |  | 1 |  |  | ― |  |  | 1 |  |  | ― |  |  | ―
Cash reductions |  |  | (6) |  |  | ― |  |  | (2) |  |  | (1) |  |  | (1) |  |  | (2) |  |  | (1)
Balance at March 31, 2013 |  | $ | 71 |  | $ | 12 |  | $ | 32 |  | $ | 13 |  | $ | 19 |  | $ | 13 |  | $ | 7
(in millions) |  | Duke Energy |  | Duke Energy Carolinas |  | Progress Energy |  | Duke Energy Progress |  | Duke Energy Florida |  | Duke Energy Ohio |  | Duke Energy Indiana
Balance at December 31, 2011 |  | $ | 61 |  | $ | 12 |  | $ | 23 |  | $ | 11 |  | $ | 12 |  | $ | 28 |  | $ | 9
Provisions / adjustments |  |  | 4 |  |  | 1 |  |  | 5 |  |  | (1) |  |  | 6 |  |  | 2 |  |  | ―
Cash reductions |  |  | (7) |  |  | ― |  |  | (4) |  |  | (1) |  |  | (3) |  |  | (5) |  |  | ―
Balance at March 31, 2012 |  | $ | 58 |  | $ | 13 |  | $ | 24 |  | $ | 9 |  | $ | 15 |  | $ | 25 |  | $ | 9
Schedule of additional possible losses in excess of recorded environmental reserves [Table Text Block] |
(in millions) |  |  |  |
Duke Energy |  |  |  |  | $ | 84
Duke Energy Carolinas |  |  |  |  |  | 29
Progress Energy |  |  |  |  |  | 7
Duke Energy Progress |  |  |  |  |  | 3
Duke Energy Florida |  |  |  |  |  | 4
Duke Energy Ohio |  |  |  |  |  | 43
Duke Energy Indiana |  |  |  |  |  | 5
Estimated costs of complying with recently issued and proposed EPA regulations [Table Text Block] |
(in millions) |  |  |  |
Duke Energy | $ | 650 |  | to | $ | 800
Duke Energy Carolinas |  | 65 |  | to |  | 85
Progress Energy |  | 7 |  | to |  | 30
Duke Energy Progress |  | 5 |  | to |  | 10
Duke Energy Florida |  | 2 |  | to |  | 20
Duke Energy Ohio |  | 40 |  | to |  | 85
Duke Energy Indiana |  | 540 |  | to |  | 600
Schedule of Litigation Reserves and Related Insurance Recoveries [Table Text Block] |
(in millions) |  | March 31, 2013 |  | December 31, 2012
Reserves for Legal and Other Matters(a) |  |  |  |  |  |
Duke Energy(b) |  | $ | 834 |  | $ | 846
Duke Energy Carolinas(b) |  |  | 743 |  |  | 751
Progress Energy |  |  | 75 |  |  | 79
Duke Energy Progress |  |  | 11 |  |  | 12
Duke Energy Florida(c) |  |  | 44 |  |  | 47
Duke Energy Indiana |  |  | 7 |  |  | 8
Probable Insurance Recoveries(d) |  |  |  |  |  |
Duke Energy(e) |  | $ | 781 |  | $ | 781
Duke Energy Carolinas(e) |  |  | 781 |  |  | 781
(a) | Reserves are classified in the respective Condensed Consolidated Balance Sheets in Other within Deferred Credits and Other Liabilities and Other within Current Liabilities.
(b) | Includes reserves for aforementioned asbestos-related injuries and damages claims.
(c) | Includes workers' compensation claims.
(d) | Insurance recoveries are classified in the respective Condensed Consolidated Balance Sheets in Other within Investments and Other Assets and Receivables.
(e) | Relates to recoveries associated with aforementioned asbestos-related injuries and damages claims.
Duke Energy Carolinas [Member] |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |
Schedule of Litigation Reserves and Related Insurance Recoveries [Table Text Block] |
(in millions) |  | March 31, 2013 |  | December 31, 2012
Reserves for Legal and Other Matters(a) |  |  |  |  |  |
Duke Energy(b) |  | $ | 834 |  | $ | 846
Duke Energy Carolinas(b) |  |  | 743 |  |  | 751
Progress Energy |  |  | 75 |  |  | 79
Duke Energy Progress |  |  | 11 |  |  | 12
Duke Energy Florida(c) |  |  | 44 |  |  | 47
Duke Energy Indiana |  |  | 7 |  |  | 8
Probable Insurance Recoveries(d) |  |  |  |  |  |
Duke Energy(e) |  | $ | 781 |  | $ | 781
Duke Energy Carolinas(e) |  |  | 781 |  |  | 781
(a) | Reserves are classified in the respective Condensed Consolidated Balance Sheets in Other within Deferred Credits and Other Liabilities and Other within Current Liabilities.
(b) | Includes reserves for aforementioned asbestos-related injuries and damages claims.
(c) | Includes workers' compensation claims.
(d) | Insurance recoveries are classified in the respective Condensed Consolidated Balance Sheets in Other within Investments and Other Assets and Receivables.
(e) | Relates to recoveries associated with aforementioned asbestos-related injuries and damages claims.
Progress Energy [Member] |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |
Schedule of Litigation Reserves and Related Insurance Recoveries [Table Text Block] |
(in millions) |  | March 31, 2013 |  | December 31, 2012
Reserves for Legal and Other Matters(a) |  |  |  |  |  |
Duke Energy(b) |  | $ | 834 |  | $ | 846
Duke Energy Carolinas(b) |  |  | 743 |  |  | 751
Progress Energy |  |  | 75 |  |  | 79
Duke Energy Progress |  |  | 11 |  |  | 12
Duke Energy Florida(c) |  |  | 44 |  |  | 47
Duke Energy Indiana |  |  | 7 |  |  | 8
Probable Insurance Recoveries(d) |  |  |  |  |  |
Duke Energy(e) |  | $ | 781 |  | $ | 781
Duke Energy Carolinas(e) |  |  | 781 |  |  | 781
(a) | Reserves are classified in the respective Condensed Consolidated Balance Sheets in Other within Deferred Credits and Other Liabilities and Other within Current Liabilities.
(b) | Includes reserves for aforementioned asbestos-related injuries and damages claims.
(c) | Includes workers' compensation claims.
(d) | Insurance recoveries are classified in the respective Condensed Consolidated Balance Sheets in Other within Investments and Other Assets and Receivables.
(e) | Relates to recoveries associated with aforementioned asbestos-related injuries and damages claims.
Duke Energy Progress [Member] |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |
Schedule of Litigation Reserves and Related Insurance Recoveries [Table Text Block] |
(in millions) |  | March 31, 2013 |  | December 31, 2012
Reserves for Legal and Other Matters(a) |  |  |  |  |  |
Duke Energy(b) |  | $ | 834 |  | $ | 846
Duke Energy Carolinas(b) |  |  | 743 |  |  | 751
Progress Energy |  |  | 75 |  |  | 79
Duke Energy Progress |  |  | 11 |  |  | 12
Duke Energy Florida(c) |  |  | 44 |  |  | 47
Duke Energy Indiana |  |  | 7 |  |  | 8
Probable Insurance Recoveries(d) |  |  |  |  |  |
Duke Energy(e) |  | $ | 781 |  | $ | 781
Duke Energy Carolinas(e) |  |  | 781 |  |  | 781
(a) | Reserves are classified in the respective Condensed Consolidated Balance Sheets in Other within Deferred Credits and Other Liabilities and Other within Current Liabilities.
(b) | Includes reserves for aforementioned asbestos-related injuries and damages claims.
(c) | Includes workers' compensation claims.
(d) | Insurance recoveries are classified in the respective Condensed Consolidated Balance Sheets in Other within Investments and Other Assets and Receivables.
(e) | Relates to recoveries associated with aforementioned asbestos-related injuries and damages claims.
Duke Energy Florida [Member] |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |
Schedule of Litigation Reserves and Related Insurance Recoveries [Table Text Block] |
(in millions) |  | March 31, 2013 |  | December 31, 2012
Reserves for Legal and Other Matters(a) |  |  |  |  |  |
Duke Energy(b) |  | $ | 834 |  | $ | 846
Duke Energy Carolinas(b) |  |  | 743 |  |  | 751
Progress Energy |  |  | 75 |  |  | 79
Duke Energy Progress |  |  | 11 |  |  | 12
Duke Energy Florida(c) |  |  | 44 |  |  | 47
Duke Energy Indiana |  |  | 7 |  |  | 8
Probable Insurance Recoveries(d) |  |  |  |  |  |
Duke Energy(e) |  | $ | 781 |  | $ | 781
Duke Energy Carolinas(e) |  |  | 781 |  |  | 781
(a) | Reserves are classified in the respective Condensed Consolidated Balance Sheets in Other within Deferred Credits and Other Liabilities and Other within Current Liabilities.
(b) | Includes reserves for aforementioned asbestos-related injuries and damages claims.
(c) | Includes workers' compensation claims.
(d) | Insurance recoveries are classified in the respective Condensed Consolidated Balance Sheets in Other within Investments and Other Assets and Receivables.
(e) | Relates to recoveries associated with aforementioned asbestos-related injuries and damages claims.
Duke Energy Indiana [Member] |  |
Valuation and Qualifying Accounts Disclosure [Line Items] |  |
Schedule of Litigation Reserves and Related Insurance Recoveries [Table Text Block] |
(in millions) |  | March 31, 2013 |  | December 31, 2012
Reserves for Legal and Other Matters(a) |  |  |  |  |  |
Duke Energy(b) |  | $ | 834 |  | $ | 846
Duke Energy Carolinas(b) |  |  | 743 |  |  | 751
Progress Energy |  |  | 75 |  |  | 79
Duke Energy Progress |  |  | 11 |  |  | 12
Duke Energy Florida(c) |  |  | 44 |  |  | 47
Duke Energy Indiana |  |  | 7 |  |  | 8
Probable Insurance Recoveries(d) |  |  |  |  |  |
Duke Energy(e) |  | $ | 781 |  | $ | 781
Duke Energy Carolinas(e) |  |  | 781 |  |  | 781
(a) | Reserves are classified in the respective Condensed Consolidated Balance Sheets in Other within Deferred Credits and Other Liabilities and Other within Current Liabilities.
(b) | Includes reserves for aforementioned asbestos-related injuries and damages claims.
(c) | Includes workers' compensation claims.
(d) | Insurance recoveries are classified in the respective Condensed Consolidated Balance Sheets in Other within Investments and Other Assets and Receivables.
(e) | Relates to recoveries associated with aforementioned asbestos-related injuries and damages claims.

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