Fair Value of Financial Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Fair Value Disclosures [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

		December 31, 2012
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Investments in available-for-sale auction rate securities(a)		$	29	$	―	$	―	$	29
Nuclear decommissioning trust fund equity securities			2,837		2,762		54		21
Nuclear decommissioning trust fund debt securities			1,405		317		1,040		48
Other trading and available-for-sale equity securities(b)			72		63		9		―
Other trading and available-for-sale debt securities(c)			602		40		562		―
Derivative assets(b)			103		18		22		63
	Total assets		5,048		3,200		1,687		161
Derivative liabilities(d)			(756)		(17)		(591)		(148)
	Net assets	$	4,292	$	3,183	$	1,096	$	13

		December 31, 2011
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Investments in available-for-sale auction rate securities(a)		$	71	$	―	$	―	$	71
Nuclear decommissioning trust fund equity securities			1,337		1,285		46		6
Nuclear decommissioning trust fund debt securities			723		109		567		47
Other trading and available-for-sale equity securities(b)			68		61		7		―
Other trading and available-for-sale debt securities(c)			382		22		360		―
Derivative assets(b)			74		43		6		25
	Total Assets		2,655		1,520		986		149
Derivative liabilities(d)			(264)		(36)		(164)		(64)
	Net Assets	$	2,391	$	1,484	$	822	$	85
(a)	Included in Other within Investments and Other Assets on the Consolidated Balance Sheets.
(b)	Included in Other within Current Assets and Other within Investments and Other Assets on the Consolidated Balance Sheet.
(c)	Included in Other within Investments and Other Assets and Short-term Investments on the Consolidated Balance Sheets.
(d)	Included in Other within Current Liabilities and Other within Deferred Credits and Other Liabilities on the Consolidated Balance Sheets.

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

	The following tables provide a reconciliation of beginning and ending balances of assets and liabilities measured at fair value on a
recurring basis where the determination of fair value includes significant unobservable inputs (Level 3).
			Year Ended December 31, 2012
(in millions)			Available-for-Sale Auction Rate Securities		Available-for-Sale NDTF Investments		Derivatives (net)		Total
Balance at December 31, 2011			$	71	$	53	$	(39)	$	85
Amounts acquired in Progress Energy Merger				―		―		(30)		(30)
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Regulated electric		―		―		23		23
		Revenue, nonregulated electric, natural gas, and other		―		―		(15)		(15)
	Total pre-tax gains included in other comprehensive income:
		Gains on available for sale securities and other		13		―		―		13
	Purchases, sales, issuances and settlements:
		Purchases		―		14		22		36
		Sales		―		(2)		―		(2)
		Issuances		―		―		(15)		(15)
		Settlements		(55)		―		(32)		(87)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			―		4		1		5
Balance at December 31, 2012			$	29	$	69	$	(85)	$	13
Pre-tax amounts included in the Consolidated Statements of Comprehensive Income related to Level 3 measurements outstanding at December 31, 2012
		Regulated electric	$	―	$	―	$	(24)		(24)
		Revenue, nonregulated electric, natural gas, and other		―		―		1		1
Total			$	―	$	―	$	(23)	$	(23)

			Year Ended December 31, 2011
(in millions)			Available-for-Sale Auction Rate Securities		Available-for-Sale NDTF Investments		Derivatives (net)		Total
Balance at December 31, 2010			$	118	$	47	$	(19)	$	146
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Regulated electric		―		―		13		13
		Revenue, nonregulated electric, natural gas, and other		―		―		(27)		(27)
	Total pre-tax gains included in other comprehensive income:
		Gains on available for sale securities and other		12		―		―		12
	Purchases, sales, issuances and settlements:
		Purchases		―		8		8		16
		Sales		―		(3)		―		(3)
		Settlements		(16)		―		(16)		(32)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			―		1		2		3
	Transfers out of Level 3			(43)		―		―		(43)
Balance at December 31, 2011			$	71	$	53	$	(39)	$	85
Pre-tax amounts included in the Consolidated Statements of Comprehensive Income related to Level 3 measurements outstanding at December 31, 2011
		Revenue, nonregulated electric, natural gas, and other		―		―		(20)		(20)
Total			$	―	$	―	$	(20)	$	(20)

			Year Ended December 31, 2010
(in millions)			Available-for-Sale Auction Rate Securities		Available-for-Sale NDTF Investments		Derivatives (net)		Total
Balance at December 31, 2009			$	198	$	―	$	25	$	223
	Total pre-tax realized or unrealized losses included in earnings:
		Revenue, nonregulated electric, natural gas, and other		―		―		(45)		(45)
		Fuel used in electric generation and purchased power-nonregulated		―		―		(13)		(13)
	Total pre-tax gains included in other comprehensive income:
		Gains on available for sale securities and other		22		―		―		22
		Losses on commodity cash flow hedges		―		―		(1)		(1)
	Net purchases, sales, issuances and settlements:			(102)		45		(3)		(60)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			―		2		18		20
Balance at December 31, 2010			$	118	$	47	$	(19)	$	146
Pre-tax amounts included in the Consolidated Statement of Operations related to Level 3 measurements outstanding at December 31, 2010
		Revenue, nonregulated electric, natural gas, and other		―		―		1		1
Total				―		―		1		1

Schedule of Long-term debt, including current

Additional Fair Value Disclosures—Long-term debt, including current maturities:
The fair value of long-term debt, including current maturities, is summarized in the following table. Judgment is required in interpreting market data to develop the estimates of fair value. Accordingly, the estimates determined are not necessarily indicative of the amounts the Duke Energy Registrants could have settled in current markets. The fair value of the long-term debt is determined using Level 2 measurements.
		As of December 31, 2012				As of December 31, 2011
(in millions)		Book Value		Fair Value		Book Value		Fair Value
Duke Energy (a)		$	39,461	$	44,001	$	20,573	$	23,053
Duke Energy Carolinas(b)		$	8,741	$	10,096	$	9,274	$	10,629
Progress Energy		$	14,428	$	16,563	$	13,152	$	15,518
Progress Energy Carolinas		$	4,840	$	5,277	$	4,206	$	4,735
Progress Energy Florida		$	5,320	$	6,222	$	4,681	$	5,633
Duke Energy Ohio		$	1,997	$	2,117	$	2,555	$	2,688
Duke Energy Indiana		$	3,702	$	4,268	$	3,459	$	4,048
(a)	Includes book value of Non-recourse long-term debt of variable interest entities of $852 million and $949 million December 31, 2012 and December 31, 2011, respectively.
(b)	Includes book value of Non-recourse long-term debt of variable interest entities of $300 million at both December 31, 2012 and December 31, 2011, respectively.

Quantitative Information Table - Level 3

	The following table includes quantitative information about the Duke Energy Registrants' derivatives classified as Level 3.
		December 31, 2012
Investment Type		Fair Value (in millions)		Valuation Technique	Unobservable Input	Range
Duke Energy
Commodity natural gas contracts		$	(53)	Discounted cash flow	Forward natural gas curves - price per MMBtu	$	2.33	$	9.99
FERC mitigation power sale agreements		$	(23)	Discounted cash flow	Forward electricity curves - price per MWh	$	25.83	-	48.69
Financial transmission rights (FTRs)		$	11	RTO market pricing	FTR price	$	23.63	-	39.22
Commodity power contracts		$	(8)	Discounted cash flow	Forward electricity curves - price per MWh	$	24.82	-	77.96
Commodity capacity contracts		$	(3)	Discounted cash flow	Forward capacity curves - price per MW day	$	95.16	-	105.36
Commodity capacity option contracts		$	3	Discounted cash flow	Forward capacity option curves - price per MW day	$	4.68	-	77.96
Reserves		$	(12)		Bid-ask spreads, implied volatility, probability of default
Duke Energy Carolinas
FERC mitigation power sale agreements		$	(12)	Discounted cash flow	Forward electricity curves - price per MWh	$	25.83	-	48.69
Progress Energy
Commodity natural gas contracts		$	(27)	Discounted cash flow	Forward natural gas curves - price per MMBtu	$	4.07	-	4.45
FERC mitigation power sale agreements		$	(11)	Discounted cash flow	Forward electricity curves - price per MWh	$	25.83	-	48.69
Progress Energy Carolinas
Commodity natural gas contracts		$	(27)	Discounted cash flow	Forward natural gas curves - price per MMBtu	$	4.07	-	4.45
FERC mitigation power sale agreements		$	(11)	Discounted cash flow	Forward electricity curves - price per MWh	$	25.83	-	48.69
Duke Energy Ohio
Financial transmission rights (FTRs)		$	1	RTO market pricing	FTR price	$	27.17	$	39.22
Commodity power contracts		$	(1)	Discounted cash flow	Forward electricity curves - price per MWh	$	25.90	-	57.50
Commodity natural gas contracts		$	5	Discounted cash flow	Forward natural gas curves - price per MMBtu	$	3.30	-	4.51
Reserves		$	(11)		Bid-ask spreads, implied volatility, probability of default
Duke Energy Indiana
Financial transmission rights (FTRs)		$	10	RTO market pricing	FTR price	$	23.63	$	35.43

Duke Energy Carolinas [Member]

Fair Value Disclosures [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

			December 31, 2012
(in millions)			Total Fair Value	Level 1		Level 2		Level 3
Investments in available-for-sale auction rate securities(a)		$	3	$	―	$	―	$	3
Nuclear decommissioning trust fund equity securities			1,592		1,523		48		21
Nuclear decommissioning trust fund debt securities			762		155		559		48
	Total assets	$	2,357	$	1,678	$	607	$	72
Derivative liabilities(c)			(12)		―		―		(12)
	Net assets	$	2,345	$	1,678	$	607	$	60

		December 31, 2011
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Investments in available-for-sale auction rate securities(a)		$	12	$	―	$	―	$	12
Nuclear decommissioning trust fund equity securities			1,337		1,285		46		6
Nuclear decommissioning trust fund debt securities			723		109		567		47
Derivative assets(b)			1		―		1		―
	Total assets	$	2,073	$	1,394	$	614	$	65
(a)	Included in Other within Investments and Other Assets on the Consolidated Balance Sheets.
(b)	Included in Other within Current Assets and Other within Investments and Other Assets on the Consolidated Balance Sheets.
(c)	Included in Other within Current Liabilities and Other within Deferred Credits and Other Liabilities on the Consolidated Balance Sheet.

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

	The following tables provide a reconciliation of beginning and ending balances of assets and liabilities measured at fair value on a
recurring basis where the determination of fair value includes significant unobservable inputs (Level 3).
			Year Ended December 31,2012
			Available-for-Sale Auction Rate Securities		Available-for-Sale NDTF Investments		Derivatives (net)		Total
Balance at December 31, 2011			$	12	$	53	$	―	$	65
	Total pre-tax gains included in other comprehensive income:
		Gains on available for sale securities and other		2		―		―		2
	Purchases, sales, issuances and settlements:
		Purchases		―		14		―		14
		Issuances		―		―		(14)		(14)
		Sales		―		(2)		―		(2)
		Settlements		(11)		―		2		(9)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			―		4		―		4
Balance at December 31, 2012			$	3	$	69	$	(12)	$	60
Pre-tax amounts included in the Consolidated Statements of Comprehensive Income related to Level 3 measurements outstanding at December 31, 2012
		Regulated electric	$	―	$	―	$	(12)		(12)
Total			$	―	$	―	$	(12)	$	(12)

			Year Ended December 31, 2011
			Available-for-Sale Auction Rate Securities		Available-for-Sale NDTF Investments		Derivatives (net)		Total
Balance at December 31, 2010			$	12	$	47	$	―	$	59
	Purchases, sales, issuances and settlements:
		Purchases		―		8		―		8
		Sales		―		(3)		―		(3)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			―		1		―		1
Balance at December 31, 2011			$	12	$	53	$	―	$	65

			Year Ended December 31, 2010
(in millions)			Available-for-Sale Auction Rate Securities		Available-for-Sale NDTF Investments		Derivatives (net)		Total
Balance at December 31, 2009			$	66	$	―	$	―	$	66
	Total pre-tax gains included in other comprehensive income:
		Gains on available for sale securities and other		12		―		―		12
	Net purchases, sales, issuances and settlements:			(66)		45		―		(21)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			―		2		―		2
Balance at December 31, 2010			$	12	$	47	$	―	$	59

Progress Energy [Member]

Fair Value Disclosures [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

		December 31, 2012
(in millions)		Total Fair Value		Level 1			Level 2		Level 3
Nuclear decommissioning trust fund equity securities		$	1,245	$	1,239	$		6	$	―
Nuclear decommissioning trust fund debt securities and other			643		162			481		―
Other trading and available-for-sale debt securities and other(a)			57		17			40		―
Derivative assets(b)			11		―			11		―
	Total assets		1,956		1,418			538		―
Derivative liabilities(c)			(440)		―			(402)		(38)
	Net assets	$	1,516	$	1,418		$	136	$	(38)

		December 31, 2011
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Nuclear decommissioning trust fund equity securities		$	1,062	$	1,061	$	1	$	―
Nuclear decommissioning trust fund debt securities and other			585		87		498		―
Other trading and available-for-sale debt securities and other(a)			20		20		―		―
Derivative assets(b)			5		―		5		―
	Total assets		1,672		1,168		504		―
Derivative liabilities(c)			(799)		―		(775)		(24)
	Net assets	$	873	$	1,168	$	(271)	$	(24)
(a)	Included in Other within Investments and Other Assets in the Consolidated Balance Sheets.
(b)	Included in Other Current Assets within Current Assets and Other within Investments and Other Assets in the Consolidated Balance Sheets.
(c)	Included in Derivative Liabilities within Current Liabilities and Other within Deferred Credits and Other Liabilities in the Consolidated Balance Sheets.

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

	The following tables provide a reconciliation of beginning and ending balances of assets and liabilities measured at fair value on a
recurring basis where the determination of fair value includes significant unobservable inputs (Level 3).
			Year Ended December 31, 2012
(in millions)			Derivatives (net)
Balance at December 31, 2011			$	(24)
	Total pre-tax realized or unrealized gains included in earnings:
		Regulated electric		1
	Purchases, sales, issuances and settlements:
		Issuances		(16)
		Settlements		4
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability			(3)
Balance at December 31, 2012			$	(38)
Pre-tax amounts included in the Consolidated Statements of Comprehensive Income related to Level 3 measurements outstanding at December 31, 2012
		Regulated electric	$	(12)
Total			$	(12)

		Year Ended December 31, 2011
(in millions)		Derivatives (net)
Balance at December 31, 2010		$	(36)
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability		(21)
	Repurchase of CVOs under settlement and tender offer		60
	Transfers into Level 3 - CVOs		(74)
	Transfers out of Level 3 - CVOs		14
	Transfers out of Level 3 - commodities		33
Balance at December 31, 2011		$	(24)

		Year Ended December 31, 2010
(in millions)		Derivatives (net)
Balance at December 31, 2009		$	(39)
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability		(44)
	Transfers out of Level 3 - commodities		47
Balance at December 31, 2010		$	(36)

Progress Energy Carolinas [Member]

Fair Value Disclosures [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

		December 31, 2012
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Nuclear decommissioning trust fund equity securities		$	811	$	811	$	―	$	―
Nuclear decommissioning trust fund debt securities and other			448		119		329		―
Other trading and available-for-sale debt securities and other(a)			3		3		―		―
Derivative assets(b)			2		―		2		―
	Total assets		1,264		933		331		―
Derivative liabilities(c)			(166)		―		(128)		(38)
	Net assets	$	1,098	$	933	$	203	$	(38)

		December 31, 2011
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Nuclear decommissioning trust fund equity securities		$	690	$	690	$	―	$	―
Nuclear decommissioning trust fund debt securities and other			398		81		317		―
Other trading and available-for-sale debt securities and other(a)			6		6		―		―
	Total assets		1,094		777		317		―
Derivative liabilities(c)			(248)		―		(224)		(24)
	Net assets	$	846	$	777	$	93	$	(24)
(a)	Included in Other within Investments and Other Assets in the Consolidated Balance Sheets.
(b)	Included in Other Current Assets within Current Assets and Other within Investments and Other Assets in the Consolidated Balance Sheets.
(c)	Included in Derivative Liabilities within Current Liabilities and Other within Deferred Credits and Other Liabilities in the Consolidated Balance Sheets

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

	The following tables provide a reconciliation of beginning and ending balances of assets and liabilities measured at fair value on a
recurring basis where the determination of fair value includes significant unobservable inputs (Level 3).
			Year Ended December 31, 2012
(in millions)			Derivatives (net)
Balance at December 31, 2011			$	(24)
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Regulated electric		1
	Purchases, sales, issuances and settlements:
		Issuances		(16)
		Settlements		4
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability			(3)
Balance at December 31, 2012			$	(38)
Pre-tax amounts included in the Consolidated Statements of Comprehensive Income related to Level 3 measurements outstanding at December 31, 2012
		Regulated electric	$	(12)
Total			$	(12)

		Year Ended December 31, 2011
(in millions)		Derivatives (net)
Balance at December 31, 2010		$	(36)
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability		(20)
	Transfers out of Level 3		32
Balance at December 31, 2011		$	(24)

		Year Ended December 31, 2010
(in millions)		Derivatives (net)
Balance at December 31, 2009		$	(27)
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability		(27)
	Transfers out of Level 3		18
Balance at December 31, 2010		$	(36)

Progress Energy Florida [Member]

Fair Value Disclosures [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

		December 31, 2012
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Nuclear decommissioning trust fund equity securities		$	435	$	429	$	6	$	―
Nuclear decommissioning trust fund debt securities and other			194		43		151		―
Other trading and available-for-sale debt securities and other(a)			43		3		40		―
Derivative assets(b)			9		―		9		―
	Total assets		681		475		206		―
Derivative liabilities(c)			(270)		―		(270)		―
	Net assets	$	411	$	475	$	(64)	$	―

		December 31, 2011
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Nuclear decommissioning trust fund equity securities		$	372	$	371	$	1	$	―
Nuclear decommissioning trust fund debt securities and other			187		6		181		―
Other trading and available-for-sale debt securities and other(a)			1		1		―		―
Derivative assets(b)			5		―		5		―
	Total assets		565		378		187		―
Derivative liabilities(c)			(499)		―		(499)		―
	Net assets	$	66	$	378	$	(312)	$	―
(a)	Included in Other within Investments and Other Assets in the Consolidated Balance Sheets.
(b)	Included in Other Current Assets within Current Assets and Other within Investments and Other Assets in the Consolidated Balance Sheets.
(c)	Included in Derivative Liabilities within Current Liabilities and Other within Deferred Credits and Other Liabilities in the Consolidated Balance Sheets

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

		The following tables provide a reconciliation of beginning and ending balances of assets and liabilities measured at fair value on a
	recurring basis where the determination of fair value includes significant unobservable inputs (Level 3):
			Year Ended December 31, 2011
(in millions)			Derivatives (net)
Balance at December 31, 2010			$	―
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability			(1)
	Transfers out of Level 3			1
Balance at December 31, 2011			$	―

		Year Ended December 31, 2010
(in millions)		Derivatives (net)
Balance at December 31, 2009		$	(12)
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability		(17)
	Transfers out of Level 3 - commodities		29
Balance at December 31, 2010		$	―

Duke Energy Ohio [Member]

Fair Value Disclosures [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

		December 31, 2012
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Derivative assets(a)		$	59	$	48	$	2	$	9
Derivative liabilities(b)			(38)		(15)		(8)		(15)
	Net assets (liabilities)	$	21	$	33	$	(6)	$	(6)

		December 31, 2011
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Derivative assets(a)		$	56	$	42	$	5	$	9
Derivative liabilities(b)			(30)		(10)		(8)		(12)
	Net assets (liabilities)	$	26	$	32	$	(3)	$	(3)
(a)	Included in Other Current Assets within Current Assets and Other within Investments and Other Assets in the Consolidated Balance Sheets.
(b)	Included in Derivative Liabilities within Current Liabilities and Other within Deferred Credits and Other Liabilities in the Consolidated Balance Sheets.

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

	The following tables provide a reconciliation of beginning and ending balances of assets and liabilities measured at fair value on a
recurring basis where the determination of fair value includes significant unobservable inputs (Level 3).
			Year Ended December 31, 2012
(in millions)			Derivatives (net)
Balance at December 31, 2011			$	(3)
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Regulated electric		1
		Revenue, nonregulated electric, natural gas, and other		(4)
	Purchases, sales, issuances and settlements:
		Settlements		1
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability			(1)
Balance at December 31, 2012			$	(6)

			Year Ended December 31, 2011
(in millions)			Derivatives (net)
Balance at December 31, 2010			$	13
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Revenue, nonregulated electric, natural gas, and other		(4)
	Purchases, sales, issuances and settlements:
		Settlements		(14)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			2
Balance at December 31, 2011			$	(3)

			Year Ended December 31, 2010
(in millions)			Derivatives (net)
Balance at December 31, 2009			$	7
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Revenue, nonregulated electric, natural gas, and other		8
		Fuel used in electric generation and purchased power nonregulated		(12)
	Total pre-tax losses included in other comprehensive income:
		Losses on commodity cash flow hedges		(1)
	Net purchases, sales, issuances and settlements:			8
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability			3
Balance at December 31, 2010			$	13
Pre-tax amounts included in the Consolidated Statements of Comprehensive Income related to Level 3 measurements outstanding at December 31, 2011:
		Revenue, nonregulated electric and other	$	17
Total			$	17

Duke Energy Indiana [Member]

Fair Value Disclosures [Line Items]

Fair Value Measurement Amounts For Assets And Liabilities

		December 31, 2012
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Available-for-sale equity securities(a)		$	49	$	49	$	―	$	―
Available-for-sale debt securities(a)			29		―		29		―
Derivative assets(b)			10		―		―		10
	Total assets		88		49		29	$	10
Derivative liabilities(c)			(63)		―		(63)		―
	Net assets (liabilities)	$	25	$	49	$	(34)	$	10

		December 31, 2011
(in millions)		Total Fair Value		Level 1		Level 2		Level 3
Available-for-sale equity securities(a)		$	46	$	46	$	―	$	―
Available-for-sale debt securities(a)			28		―		28		―
Derivative assets(b)			4		―		―		4
	Total assets		78		46		28	$	4
Derivative liabilities(c)			(69)		(1)		(68)		―
	Net assets (liabilities)	$	9	$	45	$	(40)	$	4
(a)	Included in Other within Investments and Other Assets on the Consolidated Balance Sheets.
(b)	Included in Other within Current Assets on the Consolidated Balance Sheets.
(c)	Included in Other within Current Liabilities and Other within Deferred Credits and Other Liabilities on the Consolidated Balance Sheets.

Reconciliation Of Assets And Liabilities Measured At Fair Value On A Recurring Basis Using Unobservable Inputs

	The following tables provide a reconciliation of beginning and ending balances of assets and liabilities measured at fair value on a
recurring basis where the determination of fair value includes significant unobservable inputs (Level 3).
			Year Ended December 31, 2012
(in millions)			Derivatives (net)
Balance at December 31, 2011			$	4
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Regulated electric		36
	Purchases, sales, issuances and settlements:
		Sales		22
		Settlements		(52)
Balance at December 31, 2012			$	10

			Year Ended December 31, 2011
(in millions)			Derivatives (net)
Balance at December 31, 2010			$	4
	Total pre-tax realized or unrealized gains (losses) included in earnings:
		Regulated electric		14
	Purchases, sales, issuances and settlements:
		Purchases		8
		Settlements		(21)
	Total losses included on the Consolidated Balance Sheet as regulatory asset or liability			(1)
Balance at December 31, 2011			$	4

		Year Ended December 31, 2010
(in millions)		Derivatives (net)
Balance at December 31, 2009		$	4
	Net, purchases, sales, issuances and settlements:		(15)
	Total gains included on the Consolidated Balance Sheet as regulatory asset or liability		15
Balance at December 31, 2010		$	4