Derivative Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2012

Dec. 31, 2011

Derivative Financial Instruments Tables [Abstract]

Gain or loss on the hedged items and the offsetting loss or gain on the related interest rate swaps in interest expense

		Generation										Other		Exelon
Description		Derivatives Designated as Hedging Instruments		Economic Hedges		Proprietary Trading (a)		Collateral and Netting (b)		Subtotal		Derivatives Designated as Hedging Instruments		Total
Mark-to-market derivative assets (Current Assets)	$	-	$	3	$	20	$	(19)	$	4	$	-	$	4
Mark-to-market derivative assets (Noncurrent Assets)		38	$	8	$	32		(32)		46		13		59
Total mark-to-market derivative assets	$	38	$	11	$	52	$	(51)	$	50	$	13	$	63
Mark-to-market derivative liabilities (Current Liabilities)	$	(1)	$	(1)	$	(19)	$	19	$	(2)	$	0	$	(2)
Mark-to-market derivative liabilities (Noncurrent Liabilities)		(31)	$	0	$	(32)		32		(31)		0		(31)
Total mark-to-market derivative liabilities	$	(32)	$	(1)	$	(51)	$	51	$	(33)	$	0	$	(33)
Total mark-to-market derivative net assets (liabilities)	$	6	$	10	$	1	$	0	$	17	$	13	$	30

		Gain (Loss) on Swaps						Gain (Loss) on Borrowings
		Twelve Months Ended						Twelve Months Ended
		December 31,						December 31,
Income Statement Classification		2012		2011		2010		2012		2011		2010
Interest expense (a)	$	(6)	$	1	$	4	$	(6)	$	(1)	$	(4)

__________

• For theyearended December 31, 2012, the loss on the swaps in the table above includes $12 millionreclassified to earnings, with an immaterial amount excluded from hedge effectiveness testing.

Summary of the derivative fair value

• Generation enters into interest rate derivative contracts to economically hedge risk associated with the interest rate component of commodity positions.  The characterization of the interest rate derivative contracts between the proprietary trading activity in the above table is driven by the corresponding characterization of the underlying commodity position that gives rise to the interest rate exposure.  Generation does not utilize interest rate derivatives with the objective of benefiting from shifts or changes in market interest rates.
• Represents the netting of fair value balances with the same counterparty and collateral.

		Generation								ComEd				Exelon
						Collateral
		Economic		Proprietary		and				Economic		Intercompany		Total
Derivatives		Hedges (a)		Trading		Netting(b)		Subtotal (c)		Hedges (a)(d)		Eliminations (a)		Derivatives
Mark-to-market
	derivative assets (current assets)	$	2,883	$	2,469	$	(4,418)	$	934	$	0	$	0	$	934
Mark-to-market
	derivative assets with affiliate (current assets)		226		0		0		226		0		(226)		0
Mark-to-market
	derivative assets (noncurrent assets)		1,792		724		(1,638)		878		0		0		878
Total mark-to-market
	derivative assets	$	4,901	$	3,193	$	(6,056)	$	2,038	$	0	$	(226)	$	1,812
Mark-to-market
	derivative liabilities (current liabilities)	$	(2,419)	$	(2,432)	$	4,519	$	(332)	$	(18)	$	0	$	(350)
Mark-to-market
	derivative liability with affiliate (current liabilities)		0		0		0		0		(226)		226		0
Mark-to-market
	derivative liabilities (noncurrent liabilities)		(1,080)		(689)		1,568		(201)		(49)		0		(250)
Total mark-to-market
	derivative liabilities	$	(3,499)	$	(3,121)	$	6,087	$	(533)	$	(293)	$	226	$	(600)
Total mark-to-market
	derivative net assets (liabilities)	$	1,402	$	72	$	31	$	1,505	$	(293)	$	0	$	1,212

__________

(a)       Includes current and noncurrent assets for Generation and current and noncurrent liabilities for ComEd of$226 million related to the fair value of the five-year financial swap contract between Generation and ComEd, as described above. For Generation, excludes $28 million non current liability relating to an interest rate swap in connection with a loan agreement to fund Antelope Valley as discussed above.

(b)       Represents the netting of fairvalue balances with the same counterparty and the application of collateral.

(c)       Current and noncurrent assets are shown net of collateral of $113 million and $201 million, respectively, and current and noncurrent liabilities are shown net of collateral of $(214) million and $(131) million, respectively. The total cash collateral posted, net of cash collateral receivedand offset against mark-to-market assets and liabilities was $31 million at December 31, 2012.

(d)       Includes current and noncurrent liabilities relating to floating-to-fixed energy swap contracts with unaffiliated suppliers.

		Generation										ComEd		Other				Exelon
								Collateral
		Cash Flow		Economic		Proprietary		and				Economic		Economic		Intercompany		Total
	Derivatives	Hedges (a)		Hedges		Trading		Netting(b)		Subtotal (c)		Hedges (a) (d)		Hedges		Eliminations (a)		Derivatives
Mark-to-market
	derivative assets (current assets)	$	438	$	1,195	$	217	$	(1,418)	$	432	$	0	$	0	$	0	$	432
Mark-to-market
	derivative assets with affiliate (current assets)		503		0		0		0		503		0		0		(503)		0
Mark-to-market
	derivative assets (noncurrent assets)		419		582		71		(437)		635		0		15		0		650
Mark-to-market
	derivative assets with affiliate (noncurrent assets)		191		0		0		0		191		0		0		(191)		0
Total mark-to-market
	derivative assets	$	1,551	$	1,777	$	288	$	(1,855)	$	1,761	$	0	$	15	$	(694)	$	1,082
Mark-to-market
	derivative liabilities (current liabilities)	$	(9)	$	(965)	$	(194)	$	1,065	$	(103)	$	(9)	$	0	$	0	$	(112)
Mark-to-market
	derivative liability with affiliate (current liabilities)		0		0		0		0		0		(503)		0		503		0
Mark-to-market
	derivative liabilities (noncurrent liabilities)		(4)		(186)		(70)		250		(10)		(97)		0		0		(107)
Mark-to-market
	derivative liability with affiliate (noncurrent liabilities)		0		0		0		0		0		(191)		0		191		0
Total mark-to-market
	derivative liabilities	$	(13)	$	(1,151)	$	(264)	$	1,315	$	(113)	$	(800)	$	0	$	694	$	(219)
Total mark-to-market
	derivative net assets (liabilities)	$	1,538	$	626	$	24	$	(540)	$	1,648	$	(800)	$	15	$	0	$	863

__________

(a)       Includes current and noncurrent assets for Generation and current and noncurrent liabilities for ComEd of $503 million and $191 million, respectively, related to the fair value of thefive-year financial swap contract between Generation and ComEd, as described above. For Generation, excludes $19 million non current liability relating to an interest rate swap in connection with a loan agreement to fund Antelope Valley as discussed above.

(b)       Represents the netting of fairvalue balances with the same counterparty and the application of collateral.

(c)       Current and noncurrent assets are shown net of collateral of $338million and $187million, respectively, and current and noncurrent liabilities are shown inclusive of collateral of $15 million and $0 million, respectively. The total cash collateral received net of cash collateral posted and offset against mark-to-market assets and liabilities was $540 million at December 31, 2011.

(d)       Includes current and noncurrent liabilities relating to floating-to-fixed energy swap contracts with unaffiliated suppliers.

The activity of accumulated OCI related to cash flow hedges

			Total Cash Flow Hedge OCI Activity, Net of Income Tax
			Generation			Exelon
		Income Statement Location	Energy Related Hedges			Total Cash Flow Hedges
Accumulated OCI derivative gain at
	January 1, 2011		$	1,011	(a)(d)	$	400
Effective portion of changes in fair value				504	(b)		402	(e)
Reclassifications from accumulated OCI to
	net income	Operating Revenues		(585)	(c)		(309)
Ineffective portion recognized in income		Purchased Power		(5)			(5)
Accumulated OCI derivative gain at
	December 31, 2011			925	(a)(d)		488
Effective portion of changes in fair value				432	(b)		330	(e)
Reclassifications from accumulated OCI to
	net income	Operating Revenues		(828)	(c)		(453)
Ineffective portion recognized in income		Operating Revenues		3			3
Accumulated OCI derivative gain at
	December 31, 2012		$	532	(a)(d)	$	368

__________

(a)       Includes $133 million, $420 million and $589 million of gains, net of taxes, related to the fair value of the five-year financial swap contract with ComEd for the years ended December 31, 2012, 2011 and 2010, respectively, and $3 million of gains, net of taxes, related to the fair value of the block contracts with PECOfor the year endedDecember 31, 2010.

(b)       Includes$88 million and $104 million of gains, net of taxes, related to the effective portion of changes in fair value of the five-year financial swap contract with ComEd for the years ended December 31, 2012and 2011, respectively, and $2 million of gains, net of taxes, of the effective portion of changes in fair value of the block contracts with PECO for the year ended December 31, 2010. As of the merger date, cash flow hedges were discontinued, as such, this amount represents changes in fair value prior to the merger date.

(c)       Includes $375 million and $273 millionof losses, net of taxes, reclassified from accumulated OCI to recognize gains in net income related to settlements of the five-year financial swap contract with ComEd for the years ended December 31, 2012 and 2011, respectively, and $3 million of losses, net of taxes, reclassified from accumulated OCI to recognize gains in net income related to settlements of the block contracts with PECO for the year ended December 31, 2011.

(d)       Excludes $20million of losses and $10 million of losses, net of taxes, related to interest rate swaps and treasury rate locks for the years ended December 31, 2012 and 2011, respectively.

(e)       Includes $9 million and $12 million of losses, net of taxes, related to the effective portion of changes in fair value of interest rate swaps and treasury rate locks at Generation for the year ended December 31, 2012 and 2011, respectively

Other Derivatives - Gain (loss) and reclassification

• Prior to the merger, the five-year financial swap contract between Generation and ComEd was de-designated. As a result, all prospective changes in fair value are recorded to operating revenues and eliminated in consolidation.
• Exelon and Generation have historically presented mark-to-market gains and losses within purchased power expense for all non-trading, energy-related derivatives that were not accounted for as cash flow hedges. In 2011, Exelon and Generation classified the mark-to-market gains and losses for contracts, where the underlying hedged transaction was an expected sale to hedge power, to operating revenues.

Change in fair value and reclassification of derivative contracts

	Generation							Intercompany Eliminations	Exelon
				Purchased
	Operating			Power				Operating
Year Ended December 31, 2012	Revenues		and Fuel		Total			Revenues (a)	Total
Change in fair value	$	(362)	$	215	$	(147)	$	(94)	$	(241)
Reclassification to realized at settlement		429		238		667		101		768
Net mark-to-market gains (losses)	$	67	$	453	$	520	$	7	$	527
	Exelon and Generation
				Purchased
	Operating			Power
Year Ended December 31, 2011 (As Reported)	Revenues		and Fuel		Total
Change in fair value	$	87	$	131	$	218
Reclassification to realized at settlement		(296)		(219)		(515)
Net mark-to-market (losses) (b)	$	(209)	$	(88)	$	(297)
	Exelon and Generation
				Purchased
	Operating			Power
Year Ended December 31, 2011 (Pro Forma)	Revenues		and Fuel		Total
Change in fair value	$	258	$	(40)	$	218
Reclassification to realized at settlement		(516)		1		(515)
Net mark-to-market (losses) (b)	$	(258)	$	(39)	$	(297)
	Exelon and Generation
				Purchased
	Operating			Power
Year Ended December 31, 2010 (As Reported)	Revenues		and Fuel		Total
Change in fair value	$	0	$	389	$	389
Reclassification to realized at settlement		0		(304)		(304)
Net mark-to-market (losses) (b)	$	0	$	85	$	85

		For the Years Ended
	Location on Income	December 31,
	Statement	2012		2011		2010
Change in fair value	Operating Revenue	$	(12)	$	23	$	26
Reclassification to realized at
settlement	Operating Revenue		108		(26)		(24)
Net mark-to-market gains	Operating Revenue	$	96	$	(3)	$	2

Information on Generation's credit exposure for all derivative instruments, normal purchase normal sales, and applicable payables and receivables, net of collateral and instruments that are subject to master netting agreements

	Total						Number of		Net Exposure of
	Exposure						Counterparties		Counterparties
	Before Credit		Credit		Net		Greater than 10%		Greater than 10%
Rating as of December 31, 2012	Collateral		Collateral (a)		Exposure		of Net Exposure		of Net Exposure
Investment grade	$	1,984	$	347	$	1,637		1	$	262
Non-investment grade		28		24		4		0		0
No external ratings
Internally rated - investment grade		512		10		502		1		271
Internally rated - non-investment grade		41		3		38		0		0
Total	$	2,565	$	384	$	2,181		2	$	533

Net Credit Exposure by Type of Counterparty	December 31, 2012
Investor-owned utilities, marketers and power producers		$	865
Energy cooperatives and municipalities			786
Financial Institutions			422
Other			108
Total		$	2,181

As of December 31, 2012, credit collateral held from counterparties where Generation had credit exposure included $344 million of cash and $40 million of letters of credit

Credit-Risk Related Contingent Feature		December 31, 2012
Gross Fair Value of Derivative Contracts Containing this Feature (a)	Offsetting Fair Value of In-the-Money Contracts Under Master Netting Arrangements (b)	Net Fair Value of Derivative Contracts Containing This Feature (c)
($1,849)	$1,426	($423)
Credit-Risk Related Contingent Feature		December 31, 2011
Gross Fair Value of Derivative Contracts Containing this Feature (a)	Offsetting Fair Value of In-the-Money Contracts Under Master Netting Arrangements (b)	Net Fair Value of Derivative Contracts Containing This Feature (c)
($1,014)	$928	($86)

• Amount represents the gross fair value of out-of-the-money derivative contracts containing credit-risk-related contingent features that are not fully collateralized by posted cash collateral on an individual, contract-by-contract basis ignoring the effects of master netting agreements.
• Amount represents the offsetting fair value of in-the-money derivative contracts under legallyenforceable master netting agreements with the same counterparty, which reduces the amount of any liability for which a Registrant could potentially be required to post collateral.
• Amount represents the net fair value of out-of-the-money derivative contracts containing credit-risk related contingent features after considering the mitigating effects of offsetting positions under master netting arrangements and reflects the actual net liability upon which any potential contingent collateral obligations would be based.