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.