Fair Value of Financial Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Fair value of financial liabilities recorded at the carrying amount

The following tables present the carrying amounts and fair values of the Registrants’ short-term liabilities, long-term debt, SNF obligation, and trust preferred securities (long-term debt to financing trusts or junior subordinated debentures) as of December 31, 2017 and 2016:

Exelon

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	929	$	—	$	929	$	—	$	929
Long-term debt (including amounts due within one year)(a)	34,264		—		34,735		1,970		36,705
Long-term debt to financing trusts(b)	389		—		—		431		431
SNF obligation	1,147		—		936		—		936

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	1,267	$	—	$	1,267	$	—	$	1,267
Long-term debt (including amounts due within one year)(a)	34,005		1,113		31,741		1,959		34,813
Long-term debt to financing trusts(b)	641		—		—		667		667
SNF obligation	1,024		—		732		—		732

Generation

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	2	$	—	$	2	$	—	$	2
Long-term debt (including amounts due within one year)(a)	8,990		—		7,839		1,673		9,512
SNF obligation	1,147		—		936		—		936

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	699	$	—	$	699	$	—	$	699
Long-term debt (including amounts due within one year)(a)	9,241		—		7,482		1,670		9,152
SNF obligation	1,024		—		732		—		732

ComEd

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Long-term debt (including amounts due within one year)(a)	$	7,601	$	—	$	8,418	$	—	$	8,418
Long-term debt to financing trusts(b)	205		—		—		227		227

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Long-term debt (including amounts due within one year)(a)	$	7,033	$	—	$	7,585	$	—	$	7,585
Long-term debt to financing trusts(b)	205		—		—		215		215

PECO

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Long-term debt (including amounts due within one year)(a)	$	2,903	$	—	$	3,194	$	—	$	3,194
Long-term debt to financing trusts	184		—		—		204		204

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Long-term debt (including amounts due within one year)(a)	$	2,580	$	—	$	2,794	$	—	$	2,794
Long-term debt to financing trusts	184		—		—		192		192

BGE

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	77	$	—	$	77	$	—	$	77
Long-term debt (including amounts due within one year)(a)	2,577		—		2,825		—		2,825

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	45	$	—	$	45	$	—	$	45
Long-term debt (including amounts due within one year)(a)	2,322		—		2,467		—		2,467
Long-term debt to financing trusts(b)	252		—		—		260		260

PHI (Successor)

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	350	$	—	$	350	$	—	$	350
Long-term debt (including amounts due within one year)(a)	5,874		—		5,722		297		6,019

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	522	$	—	$	522	$	—	$	522
Long-term debt (including amounts due within one year)(a)	5,898		—		5,520		289		5,809

Pepco

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	26	$	—	$	26	$	—	$	26
Long-term debt (including amounts due within one year)(a)	2,540		—		3,114		9		3,123

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	23	$	—	$	23	$	—	$	23
Long-term debt (including amounts due within one year)(a)	2,349		—		2,788		8		2,796

DPL

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	216	$	—	$	216	$	—	$	216
Long-term debt (including amounts due within one year)(a)	1,300		—		1,393		—		1,393

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Long-term debt (including amounts due within one year)(a)	$	1,340	$	—	$	1,383	$	—	$	1,383

ACE

	December 31, 2017
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Short-term liabilities	$	108	$	—	$	108	$	—	$	108
Long-term debt (including amounts due within one year)(a)	1,121		—		949		288		1,237

	December 31, 2016
	Carrying Amount		Fair Value
			Level 1		Level 2		Level 3		Total
Long-term debt (including amounts due within one year)(a)	$	1,155	$	—	$	1,007	$	280	$	1,287

__________

(a) Includes unamortized debt issuance costs which are not fair valued of $201 million, $60 million, $52 million, $17 million, $17 million, $6 million, $32 million, $11 million and $5 million for Exelon, Generation, ComEd, PECO, BGE, PHI, Pepco, DPL and ACE respectively, as of December 31, 2017. Includes unamortized debt issuance costs which are not fair valued of $200 million, $64 million, $46 million, $15 million, $15 million, $2 million, $30 million, $11 million and $6 million for Exelon, Generation, ComEd, PECO, BGE, PHI, Pepco, DPL and ACE respectively, as of December 31, 2016.

(b) Includes unamortized debt issuance costs which are not fair valued of $1 million and $1 million for Exelon and ComEd, respectively, as of December 31, 2017. Includes unamortized debt issuance costs which are not fair valued of $7 million, $1 million, and $6 million for Exelon, ComEd and BGE, respectively, as of December 31, 2016.

Assets and liabilities measured and recorded at fair value on recurring basis

PHI, Pepco, DPL and ACE

The following tables present assets and liabilities measured and recorded at fair value on PHI's, Pepco's, DPL's and ACE's Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2017 and 2016:

	Successor
	As of December 31, 2017											As of December 31, 2016
PHI	Level 1			Level 2			Level 3		Total			Level 1			Level 2			Level 3		Total
Assets
Cash equivalents(a)	$	83		$	—		$	—	$	83		$	217		$	—		$	—	$	217
Mark-to-market derivative assets(b)	—			—			—		—			2			—			—		2
Effect of netting and allocation of collateral	—			—			—		—			(2		)	—			—		(2		)
Mark-to-market derivative assets subtotal	—			—			—		—			—			—			—		—
Rabbi trust investments
Cash equivalents	72			—			—		72			73			—			—		73
Fixed income	—			12			—		12			—			16			—		16
Life insurance contracts	—			23			22		45			—			22			20		42
Rabbi trust investments subtotal	72			35			22		129			73			38			20		131
Total assets	155			35			22		212			290			38			20		348
Liabilities
Deferred compensation obligation	—			(25		)	—		(25		)	—			(28		)	—		(28		)
Mark-to-market derivative liabilities(b)	(1		)	—			—		(1		)	—			—			—		—
Effect of netting and allocation of collateral	1			—			—		1			—			—			—		—
Mark-to-market derivative liabilities subtotal	—			—			—		—			—			—			—		—
Total liabilities	—			(25		)	—		(25		)	—			(28		)	—		(28		)
Total net assets	$	155		$	10		$	22	$	187		$	290		$	10		$	20	$	320

	Pepco										DPL											ACE
As of December 31, 2017	Level 1		Level 2			Level 3		Total			Level 1			Level 2			Level 3		Total			Level 1		Level 2		Level 3		Total
Assets
Cash equivalents(a)	$	36	$	—		$	—	$	36		$	—		$	—		$	—	$	—		$	29	$	—	$	—	$	29
Rabbi trust investments
Cash equivalents	44		—			—		44			—			—			—		—			—		—		—		—
Fixed income	—		12			—		12			—			—			—		—			—		—		—		—
Life insurance contracts	—		23			22		45			—			—			—		—			—		—		—		—
Rabbi trust investments subtotal	44		35			22		101			—			—			—		—			—		—		—		—
Total assets	80		35			22		137			—			—			—		—			29		—		—		29
Liabilities
Deferred compensation obligation	—		(4		)	—		(4		)	—			(1		)	—		(1		)	—		—		—		—
Mark-to-market derivative liabilities (b)	—		—			—		—			(1		)	—			—		(1		)	—		—		—		—
Effect of netting and allocation of collateral	—		—			—		—			1			—			—		1			—		—		—		—
Mark-to-market derivative liabilities subtotal	—		—			—		—			—			—			—		—			—		—		—		—
Total liabilities	—		(4		)	—		(4		)	—			(1		)	—		(1		)	—		—		—		—
Total net assets (liabilities)	$	80	$	31		$	22	$	133		$	—		$	(1	)	$	—	$	(1	)	$	29	$	—	$	—	$	29

	Pepco										DPL											ACE
As of December 31, 2016	Level 1		Level 2			Level 3		Total			Level 1			Level 2			Level 3		Total			Level 1		Level 2		Level 3		Total
Assets
Cash equivalents(a)	$	33	$	—		$	—	$	33		$	42		$	—		$	—	$	42		$	130	$	—	$	—	$	130
Mark-to-market derivative assets(b)	—		—			—		—			2			—			—		2			—		—		—		—
Effect of netting and allocation of collateral	—		—			—		—			(2		)	—			—		(2		)	—		—		—		—
Mark-to-market derivative assets subtotal	—		—			—		—			—			—			—		—			—		—		—		—
Rabbi trust investments
Cash equivalents	43		—			—		43			—			—			—		—			—		—		—		—
Fixed income	—		16			—		16			—			—			—		—			—		—		—		—
Life insurance contracts	—		22			19		41			—			—			—		—			—		—		—		—
Rabbi trust investments subtotal	43		38			19		100			—			—			—		—			—		—		—		—
Total assets	76		38			19		133			42			—			—		42			130		—		—		130
Liabilities
Deferred compensation obligation	—		(5		)	—		(5		)	—			(1		)	—		(1		)	—		—		—		—
Total liabilities	—		(5		)	—		(5		)	—			(1		)	—		(1		)	—		—		—		—
Total net assets (liabilities)	$	76	$	33		$	19	$	128		$	42		$	(1	)	$	—	$	41		$	130	$	—	$	—	$	130

_______

(a) PHI excludes cash of $12 million and $19 million at December 31, 2017 and 2016 and includes long term restricted cash of $23 million at both December 31, 2017 and 2016 which is reported in Other deferred debits on the Consolidated Balance Sheets.  Pepco excludes cash of $4 million and $9 million at December 31, 2017 and 2016. DPL excludes cash of $2 million and $4 million at December 31, 2017 and 2016. ACE excludes cash of $2 million and $3 million at December 31, 2017 and 2016 and includes long-term restricted cash of $23 million at both December 31, 2017 and 2016 which is reported in Other deferred debits on the Consolidated Balance Sheets.

(b) Represents natural gas futures purchased by DPL as part of a natural gas hedging program approved by the DPSC.

ComEd, PECO and BGE

The following tables present assets and liabilities measured and recorded at fair value on ComEd's, PECO's and BGE's Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2017 and 2016:

	ComEd											PECO										BGE
As of December 31, 2017	Level 1		Level 2			Level 3			Total			Level 1		Level 2			Level 3		Total			Level 1		Level 2			Level 3		Total
Assets
Cash equivalents(a)	$	98	$	—		$	—		$	98		$	228	$	—		$	—	$	228		$	—	$	—		$	—	$	—
Rabbi trust investments
Mutual funds	—		—			—			—			7		—			—		7			6		—			—		6
Life insurance contracts	—		—			—			—			—		10			—		10			—		—			—		—
Rabbi trust investments subtotal	—		—			—			—			7		10			—		17			6		—			—		6
Total assets	98		—			—			98			235		10			—		245			6		—			—		6
Liabilities
Deferred compensation obligation	—		(8		)	—			(8		)	—		(11		)	—		(11		)	—		(5		)	—		(5		)
Mark-to-market derivative liabilities(b)	—		—			(256		)	(256		)	—		—			—		—			—		—			—		—
Total liabilities	—		(8		)	(256		)	(264		)	—		(11		)	—		(11		)	—		(5		)	—		(5		)
Total net assets (liabilities)	$	98	$	(8	)	$	(256	)	$	(166	)	$	235	$	(1	)	$	—	$	234		$	6	$	(5	)	$	—	$	1

	ComEd											PECO										BGE
As of December 31, 2016	Level 1		Level 2			Level 3			Total			Level 1		Level 2			Level 3		Total			Level 1		Level 2			Level 3		Total
Assets
Cash equivalents(a)	$	20	$	—		$	—		$	20		$	45	$	—		$	—	$	45		$	36	$	—		$	—	$	36
Rabbi trust investments
Mutual funds	—		—			—			—			7		—			—		7			4		—			—		4
Life insurance contracts	—		—			—			—			—		10			—		10			—		—			—		—
Rabbi trust investments subtotal	—		—			—			—			7		10			—		17			4		—			—		4
Total assets	20		—			—			20			52		10			—		62			40		—			—		40
Liabilities
Deferred compensation obligation	—		(8		)	—			(8		)	—		(11		)	—		(11		)	—		(4		)	—		(4		)
Mark-to-market derivative liabilities(b)	—		—			(258		)	(258		)	—		—			—		—			—		—			—		—
Total liabilities	—		(8		)	(258		)	(266		)	—		(11		)	—		(11		)	—		(4		)	—		(4		)
Total net assets (liabilities)	$	20	$	(8	)	$	(258	)	$	(246	)	$	52	$	(1	)	$	—	$	51		$	40	$	(4	)	$	—	$	36

__________

(a) ComEd excludes cash of $45 million and $36 million at December 31, 2017 and 2016 and restricted cash of $2 million at December 31, 2016 and includes long-term restricted cash of $62 million at December 31, 2017, which is reported in Other deferred debits on the Consolidated Balance Sheets.  PECO excludes cash of $47 million and $22 million at December 31, 2017 and 2016.  BGE excludes cash of $17 million and $13 million at December 31, 2017 and 2016 and restricted cash of $1 million at December 31, 2017 and includes long-term restricted cash of $2 million at December 31, 2016, which is reported in Other deferred debits on the Consolidated Balance Sheets.

(b) The Level 3 balance consists of the current and noncurrent liability of $21 million and $235 million, respectively, at December 31, 2017, and $19 million and $239 million, respectively, at December 31, 2016, related to floating-to-fixed energy swap contracts with unaffiliated suppliers.

The following tables present assets and liabilities measured and recorded at fair value on Exelon's and Generation’s Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2017 and 2016:

	Generation										Exelon
As of December 31, 2017	Level 1		Level 2		Level 3		Not subject to leveling		Total		Level 1		Level 2		Level 3		Not subject to leveling		Total
Assets
Cash equivalents(a)	$	168	$	—	$	—	$	—	$	168	$	656	$	—	$	—	$	—	$	656

	Generation									Exelon
As of December 31, 2017	Level 1		Level 2		Level 3		Not subject to leveling	Total		Level 1		Level 2		Level 3		Not subject to leveling	Total
NDT fund investments
Cash equivalents(b)	135		85		—		—	220		135		85		—		—	220
Equities	4,163		915		—		2,176	7,254		4,163		915		—		2,176	7,254
Fixed income
Corporate debt	—		1,614		251		—	1,865		—		1,614		251		—	1,865
U.S. Treasury and agencies	1,917		52		—		—	1,969		1,917		52		—		—	1,969
Foreign governments	—		82		—		—	82		—		82		—		—	82
State and municipal debt	—		263		—		—	263		—		263		—		—	263
Other(c)	—		47		—		510	557		—		47		—		510	557
Fixed income subtotal	1,917		2,058		251		510	4,736		1,917		2,058		251		510	4,736
Middle market lending	—		—		397		131	528		—		—		397		131	528
Private equity	—		—		—		222	222		—		—		—		222	222
Real estate	—		—		—		471	471		—		—		—		471	471
NDT fund investments subtotal(d)	6,215		3,058		648		3,510	13,431		6,215		3,058		648		3,510	13,431
Pledged assets for Zion Station decommissioning
Cash equivalents	2		—		—		—	2		2		—		—		—	2
Equities	—		1		—		—	1		—		1		—		—	1
Middle market lending	—		—		12		24	36		—		—		12		24	36
Pledged assets for Zion Station decommissioning subtotal	2		1		12		24	39		2		1		12		24	39
Rabbi trust investments
Cash equivalents	5		—		—		—	5		77		—		—		—	77
Mutual funds	23		—		—		—	23		58		—		—		—	58
Fixed income	—		—		—		—	—		—		12		—		—	12
Life insurance contracts	—		22		—		—	22		—		71		22		—	93
Rabbi trust investments subtotal	28		22		—		—	50		135		83		22		—	240
Commodity derivative assets
Economic hedges	557		2,378		1,290		—	4,225		557		2,378		1,290		—	4,225
Proprietary trading	2		31		35		—	68		2		31		35		—	68
Effect of netting and allocation of collateral(e)(f)	(585	)	(1,769	)	(635	)	—	(2,989	)	(585	)	(1,769	)	(635	)	—	(2,989	)
Commodity derivative assets subtotal	(26	)	640		690		—	1,304		(26	)	640		690		—	1,304

	Generation														Exelon
As of December 31, 2017	Level 1			Level 2			Level 3			Not subject to leveling		Total			Level 1			Level 2			Level 3			Not subject to leveling		Total
Interest rate and foreign currency derivative assets
Derivatives designated as hedging instruments	—			3			—			—		3			—			6			—			—		6
Economic hedges	—			10			—			—		10			—			10			—			—		10
Effect of netting and allocation of collateral	(2		)	(5		)	—			—		(7		)	(2		)	(5		)	—			—		(7		)
Interest rate and foreign currency derivative assets subtotal	(2		)	8			—			—		6			(2		)	11			—			—		9
Other investments	—			—			37			—		37			—			—			37			—		37
Total assets	6,385			3,729			1,387			3,534		15,035			6,980			3,793			1,409			3,534		15,716
Liabilities
Commodity derivative liabilities
Economic hedges	(712		)	(2,226		)	(845		)	—		(3,783		)	(713		)	(2,226		)	(1,101		)	—		(4,040		)
Proprietary trading	(2		)	(42		)	(9		)	—		(53		)	(2		)	(42		)	(9		)	—		(53		)
Effect of netting and allocation of collateral(e)(f)	650			2,089			716			—		3,455			651			2,089			716			—		3,456
Commodity derivative liabilities subtotal	(64		)	(179		)	(138		)	—		(381		)	(64		)	(179		)	(394		)	—		(637		)
Interest rate and foreign currency derivative liabilities
Derivatives designated as hedging instruments	—			(2		)	—			—		(2		)	—			(2		)	—			—		(2		)
Economic hedges	(1		)	(8		)	—			—		(9		)	(1		)	(8		)	—			—		(9		)
Effect of netting and allocation of collateral	2			5			—			—		7			2			5			—			—		7
Interest rate and foreign currency derivative liabilities subtotal	1			(5		)	—			—		(4		)	1			(5		)	—			—		(4		)
Deferred compensation obligation	—			(38		)	—			—		(38		)	—			(145		)	—			—		(145		)
Total liabilities	(63		)	(222		)	(138		)	—		(423		)	(63		)	(329		)	(394		)	—		(786		)
Total net assets	$	6,322		$	3,507		$	1,249		$	3,534	$	14,612		$	6,917		$	3,464		$	1,015		$	3,534	$	14,930

	Generation										Exelon
As of December 31, 2016	Level 1		Level 2		Level 3		Not subject to leveling		Total		Level 1		Level 2		Level 3		Not subject to leveling		Total
Assets
Cash equivalents(a)	$	39	$	—	$	—	$	—	$	39	$	373	$	—	$	—	$	—	$	373
NDT fund investments

	Generation									Exelon
As of December 31, 2016	Level 1		Level 2		Level 3		Not subject to leveling	Total		Level 1		Level 2		Level 3		Not subject to leveling	Total
Cash equivalents(b)	110		19		—		—	129		110		19		—		—	129
Equities	3,551		452		—		2,011	6,014		3,551		452		—		2,011	6,014
Fixed income
Corporate debt	—		1,554		250		—	1,804		—		1,554		250		—	1,804
U.S. Treasury and agencies	1,291		29		—		—	1,320		1,291		29		—		—	1,320
Foreign governments	—		37		—		—	37		—		37		—		—	37
State and municipal debt	—		264		—		—	264		—		264		—		—	264
Other(c)	—		59		—		493	552		—		59		—		493	552
Fixed income subtotal	1,291		1,943		250		493	3,977		1,291		1,943		250		493	3,977
Middle market lending	—		—		427		71	498		—		—		427		71	498
Private equity	—		—		—		148	148		—		—		—		148	148
Real estate	—		—		—		326	326		—		—		—		326	326
NDT fund investments subtotal(d)	4,952		2,414		677		3,049	11,092		4,952		2,414		677		3,049	11,092
Pledged assets for Zion Station decommissioning
Cash equivalents	11		—		—		—	11		11		—		—		—	11
Equities	—		2		—		—	2		—		2		—		—	2
Fixed Income - U.S. Treasury and agencies	16		1		—		—	17		16		1		—		—	17
Middle market lending	—		—		19		64	83		—		—		19		64	83
Pledged assets for Zion Station decommissioning subtotal	27		3		19		64	113		27		3		19		64	113
Rabbi trust investments
Cash equivalents	2		—		—		—	2		74		—		—		—	74
Mutual funds	19		—		—		—	19		50		—		—		—	50
Fixed income	—		—		—		—	—		—		16		—		—	16
Life insurance contracts	—		18		—		—	18		—		64		20		—	84
Rabbi trust investments subtotal	21		18		—		—	39		124		80		20		—	224
Commodity derivative assets
Economic hedges	1,356		2,505		1,229		—	5,090		1,358		2,505		1,229		—	5,092
Proprietary trading	3		50		23		—	76		3		50		23		—	76
Effect of netting and allocation of collateral(e)(f)	(1,162	)	(2,142	)	(481	)	—	(3,785	)	(1,164	)	(2,142	)	(481	)	—	(3,787	)
Commodity derivative assets subtotal	197		413		771		—	1,381		197		413		771		—	1,381

	Generation														Exelon
As of December 31, 2016	Level 1			Level 2			Level 3			Not subject to leveling		Total			Level 1			Level 2			Level 3			Not subject to leveling		Total
Interest rate and foreign currency derivative assets
Derivatives designated as hedging instruments	—			—			—			—		—			—			16			—			—		16
Economic hedges	—			28			—			—		28			—			28			—			—		28
Proprietary trading	3			2			—			—		5			3			2			—			—		5
Effect of netting and allocation of collateral	(2		)	(19		)	—			—		(21		)	(2		)	(19		)	—			—		(21		)
Interest rate and foreign currency derivative assets subtotal	1			11			—			—		12			1			27			—			—		28
Other investments	—			—			42			—		42			—			—			42			—		42
Total assets	5,237			2,859			1,509			3,113		12,718			5,674			2,937			1,529			3,113		13,253
Liabilities
Commodity derivative liabilities
Economic hedges	(1,267		)	(2,378		)	(794		)	—		(4,439		)	(1,267		)	(2,378		)	(1,052		)	—		(4,697		)
Proprietary trading	(3		)	(50		)	(26		)	—		(79		)	(3		)	(50		)	(26		)	—		(79		)
Effect of netting and allocation of collateral(e)(f)	1,233			2,339			542			—		4,114			1,233			2,339			542			—		4,114
Commodity derivative liabilities subtotal	(37		)	(89		)	(278		)	—		(404		)	(37		)	(89		)	(536		)	—		(662		)
Interest rate and foreign currency derivative liabilities
Derivatives designated as hedging instruments	—			(10		)	—			—		(10		)	—			(10		)	—			—		(10		)
Economic hedges	—			(21		)	—			—		(21		)	—			(21		)	—			—		(21		)
Proprietary trading	(4		)	—			—			—		(4		)	(4		)	—			—			—		(4		)
Effect of netting and allocation of collateral	4			19			—			—		23			4			19			—			—		23
Interest rate and foreign currency derivative liabilities subtotal	—			(12		)	—			—		(12		)	—			(12		)	—			—		(12		)
Deferred compensation obligation	—			(34		)	—			—		(34		)	—			(136		)	—			—		(136		)
Total liabilities	(37		)	(135		)	(278		)	—		(450		)	(37		)	(237		)	(536		)	—		(810		)
Total net assets	$	5,200		$	2,724		$	1,231		$	3,113	$	12,268		$	5,637		$	2,700		$	993		$	3,113	$	12,443

__________

(a) Generation excludes cash of $259 million and $252 million at December 31, 2017 and 2016 and restricted cash of $127 million and $157 million at December 31, 2017 and 2016.  Exelon excludes cash of $389 million and $360 million at December 31, 2017 and 2016 and restricted cash of $145 million and $180 million at December 31, 2017 and 2016 and includes long-term restricted cash of $85 million and $25 million at December 31, 2017 and 2016, which is reported in Other deferred debits on the Consolidated Balance Sheets.

(b) Includes $77 million and $29 million of cash received from outstanding repurchase agreements at December 31, 2017 and 2016, respectively, and is offset by an obligation to repay upon settlement of the agreement as discussed in (d) below.

(c) Includes derivative instruments of less than $1 million and $(2) million, which have a total notional amount of $811 million and $933 million at December 31, 2017 and 2016, respectively. The notional principal amounts for these instruments provide one measure of the transaction volume outstanding as of the fiscal years ended and do not represent the amount of the company's exposure to credit or market loss.

(d) Excludes net liabilities of $82 million and $31 million at December 31, 2017 and 2016, respectively. These items consist of receivables related to pending securities sales, interest and dividend receivables, repurchase agreement obligations, and payables related to pending securities purchases. The repurchase agreements are generally short-term in nature with durations generally of 30 days or less.

(e) Collateral posted/(received) from counterparties totaled $65 million, $320 million and $81 million allocated to Level 1, Level 2 and Level 3 mark-to-market derivatives, respectively, as of December 31, 2017. Collateral posted/(received) from counterparties totaled $71 million, $197 million and $61 million allocated to Level 1, Level 2 and Level 3 mark-to-market derivatives, respectively, as of December 31, 2016.

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

PHI, Pepco, DPL and ACE

The following tables present assets and liabilities measured and recorded at fair value on PHI's, Pepco's, DPL's and ACE's Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2017 and 2016:

	Successor
	As of December 31, 2017											As of December 31, 2016
PHI	Level 1			Level 2			Level 3		Total			Level 1			Level 2			Level 3		Total
Assets
Cash equivalents(a)	$	83		$	—		$	—	$	83		$	217		$	—		$	—	$	217
Mark-to-market derivative assets(b)	—			—			—		—			2			—			—		2
Effect of netting and allocation of collateral	—			—			—		—			(2		)	—			—		(2		)
Mark-to-market derivative assets subtotal	—			—			—		—			—			—			—		—
Rabbi trust investments
Cash equivalents	72			—			—		72			73			—			—		73
Fixed income	—			12			—		12			—			16			—		16
Life insurance contracts	—			23			22		45			—			22			20		42
Rabbi trust investments subtotal	72			35			22		129			73			38			20		131
Total assets	155			35			22		212			290			38			20		348
Liabilities
Deferred compensation obligation	—			(25		)	—		(25		)	—			(28		)	—		(28		)
Mark-to-market derivative liabilities(b)	(1		)	—			—		(1		)	—			—			—		—
Effect of netting and allocation of collateral	1			—			—		1			—			—			—		—
Mark-to-market derivative liabilities subtotal	—			—			—		—			—			—			—		—
Total liabilities	—			(25		)	—		(25		)	—			(28		)	—		(28		)
Total net assets	$	155		$	10		$	22	$	187		$	290		$	10		$	20	$	320

	Pepco										DPL											ACE
As of December 31, 2017	Level 1		Level 2			Level 3		Total			Level 1			Level 2			Level 3		Total			Level 1		Level 2		Level 3		Total
Assets
Cash equivalents(a)	$	36	$	—		$	—	$	36		$	—		$	—		$	—	$	—		$	29	$	—	$	—	$	29
Rabbi trust investments
Cash equivalents	44		—			—		44			—			—			—		—			—		—		—		—
Fixed income	—		12			—		12			—			—			—		—			—		—		—		—
Life insurance contracts	—		23			22		45			—			—			—		—			—		—		—		—
Rabbi trust investments subtotal	44		35			22		101			—			—			—		—			—		—		—		—
Total assets	80		35			22		137			—			—			—		—			29		—		—		29
Liabilities
Deferred compensation obligation	—		(4		)	—		(4		)	—			(1		)	—		(1		)	—		—		—		—
Mark-to-market derivative liabilities (b)	—		—			—		—			(1		)	—			—		(1		)	—		—		—		—
Effect of netting and allocation of collateral	—		—			—		—			1			—			—		1			—		—		—		—
Mark-to-market derivative liabilities subtotal	—		—			—		—			—			—			—		—			—		—		—		—
Total liabilities	—		(4		)	—		(4		)	—			(1		)	—		(1		)	—		—		—		—
Total net assets (liabilities)	$	80	$	31		$	22	$	133		$	—		$	(1	)	$	—	$	(1	)	$	29	$	—	$	—	$	29

	Pepco										DPL											ACE
As of December 31, 2016	Level 1		Level 2			Level 3		Total			Level 1			Level 2			Level 3		Total			Level 1		Level 2		Level 3		Total
Assets
Cash equivalents(a)	$	33	$	—		$	—	$	33		$	42		$	—		$	—	$	42		$	130	$	—	$	—	$	130
Mark-to-market derivative assets(b)	—		—			—		—			2			—			—		2			—		—		—		—
Effect of netting and allocation of collateral	—		—			—		—			(2		)	—			—		(2		)	—		—		—		—
Mark-to-market derivative assets subtotal	—		—			—		—			—			—			—		—			—		—		—		—
Rabbi trust investments
Cash equivalents	43		—			—		43			—			—			—		—			—		—		—		—
Fixed income	—		16			—		16			—			—			—		—			—		—		—		—
Life insurance contracts	—		22			19		41			—			—			—		—			—		—		—		—
Rabbi trust investments subtotal	43		38			19		100			—			—			—		—			—		—		—		—
Total assets	76		38			19		133			42			—			—		42			130		—		—		130
Liabilities
Deferred compensation obligation	—		(5		)	—		(5		)	—			(1		)	—		(1		)	—		—		—		—
Total liabilities	—		(5		)	—		(5		)	—			(1		)	—		(1		)	—		—		—		—
Total net assets (liabilities)	$	76	$	33		$	19	$	128		$	42		$	(1	)	$	—	$	41		$	130	$	—	$	—	$	130

_______

(a) PHI excludes cash of $12 million and $19 million at December 31, 2017 and 2016 and includes long term restricted cash of $23 million at both December 31, 2017 and 2016 which is reported in Other deferred debits on the Consolidated Balance Sheets.  Pepco excludes cash of $4 million and $9 million at December 31, 2017 and 2016. DPL excludes cash of $2 million and $4 million at December 31, 2017 and 2016. ACE excludes cash of $2 million and $3 million at December 31, 2017 and 2016 and includes long-term restricted cash of $23 million at both December 31, 2017 and 2016 which is reported in Other deferred debits on the Consolidated Balance Sheets.

(b) Represents natural gas futures purchased by DPL as part of a natural gas hedging program approved by the DPSC.

ComEd, PECO and BGE

The following tables present assets and liabilities measured and recorded at fair value on ComEd's, PECO's and BGE's Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2017 and 2016:

	ComEd											PECO										BGE
As of December 31, 2017	Level 1		Level 2			Level 3			Total			Level 1		Level 2			Level 3		Total			Level 1		Level 2			Level 3		Total
Assets
Cash equivalents(a)	$	98	$	—		$	—		$	98		$	228	$	—		$	—	$	228		$	—	$	—		$	—	$	—
Rabbi trust investments
Mutual funds	—		—			—			—			7		—			—		7			6		—			—		6
Life insurance contracts	—		—			—			—			—		10			—		10			—		—			—		—
Rabbi trust investments subtotal	—		—			—			—			7		10			—		17			6		—			—		6
Total assets	98		—			—			98			235		10			—		245			6		—			—		6
Liabilities
Deferred compensation obligation	—		(8		)	—			(8		)	—		(11		)	—		(11		)	—		(5		)	—		(5		)
Mark-to-market derivative liabilities(b)	—		—			(256		)	(256		)	—		—			—		—			—		—			—		—
Total liabilities	—		(8		)	(256		)	(264		)	—		(11		)	—		(11		)	—		(5		)	—		(5		)
Total net assets (liabilities)	$	98	$	(8	)	$	(256	)	$	(166	)	$	235	$	(1	)	$	—	$	234		$	6	$	(5	)	$	—	$	1

	ComEd											PECO										BGE
As of December 31, 2016	Level 1		Level 2			Level 3			Total			Level 1		Level 2			Level 3		Total			Level 1		Level 2			Level 3		Total
Assets
Cash equivalents(a)	$	20	$	—		$	—		$	20		$	45	$	—		$	—	$	45		$	36	$	—		$	—	$	36
Rabbi trust investments
Mutual funds	—		—			—			—			7		—			—		7			4		—			—		4
Life insurance contracts	—		—			—			—			—		10			—		10			—		—			—		—
Rabbi trust investments subtotal	—		—			—			—			7		10			—		17			4		—			—		4
Total assets	20		—			—			20			52		10			—		62			40		—			—		40
Liabilities
Deferred compensation obligation	—		(8		)	—			(8		)	—		(11		)	—		(11		)	—		(4		)	—		(4		)
Mark-to-market derivative liabilities(b)	—		—			(258		)	(258		)	—		—			—		—			—		—			—		—
Total liabilities	—		(8		)	(258		)	(266		)	—		(11		)	—		(11		)	—		(4		)	—		(4		)
Total net assets (liabilities)	$	20	$	(8	)	$	(258	)	$	(246	)	$	52	$	(1	)	$	—	$	51		$	40	$	(4	)	$	—	$	36

__________

(a) ComEd excludes cash of $45 million and $36 million at December 31, 2017 and 2016 and restricted cash of $2 million at December 31, 2016 and includes long-term restricted cash of $62 million at December 31, 2017, which is reported in Other deferred debits on the Consolidated Balance Sheets.  PECO excludes cash of $47 million and $22 million at December 31, 2017 and 2016.  BGE excludes cash of $17 million and $13 million at December 31, 2017 and 2016 and restricted cash of $1 million at December 31, 2017 and includes long-term restricted cash of $2 million at December 31, 2016, which is reported in Other deferred debits on the Consolidated Balance Sheets.

(b) The Level 3 balance consists of the current and noncurrent liability of $21 million and $235 million, respectively, at December 31, 2017, and $19 million and $239 million, respectively, at December 31, 2016, related to floating-to-fixed energy swap contracts with unaffiliated suppliers.

The following tables present assets and liabilities measured and recorded at fair value on Exelon's and Generation’s Consolidated Balance Sheets on a recurring basis and their level within the fair value hierarchy as of December 31, 2017 and 2016:

	Generation										Exelon
As of December 31, 2017	Level 1		Level 2		Level 3		Not subject to leveling		Total		Level 1		Level 2		Level 3		Not subject to leveling		Total
Assets
Cash equivalents(a)	$	168	$	—	$	—	$	—	$	168	$	656	$	—	$	—	$	—	$	656

	Generation									Exelon
As of December 31, 2017	Level 1		Level 2		Level 3		Not subject to leveling	Total		Level 1		Level 2		Level 3		Not subject to leveling	Total
NDT fund investments
Cash equivalents(b)	135		85		—		—	220		135		85		—		—	220
Equities	4,163		915		—		2,176	7,254		4,163		915		—		2,176	7,254
Fixed income
Corporate debt	—		1,614		251		—	1,865		—		1,614		251		—	1,865
U.S. Treasury and agencies	1,917		52		—		—	1,969		1,917		52		—		—	1,969
Foreign governments	—		82		—		—	82		—		82		—		—	82
State and municipal debt	—		263		—		—	263		—		263		—		—	263
Other(c)	—		47		—		510	557		—		47		—		510	557
Fixed income subtotal	1,917		2,058		251		510	4,736		1,917		2,058		251		510	4,736
Middle market lending	—		—		397		131	528		—		—		397		131	528
Private equity	—		—		—		222	222		—		—		—		222	222
Real estate	—		—		—		471	471		—		—		—		471	471
NDT fund investments subtotal(d)	6,215		3,058		648		3,510	13,431		6,215		3,058		648		3,510	13,431
Pledged assets for Zion Station decommissioning
Cash equivalents	2		—		—		—	2		2		—		—		—	2
Equities	—		1		—		—	1		—		1		—		—	1
Middle market lending	—		—		12		24	36		—		—		12		24	36
Pledged assets for Zion Station decommissioning subtotal	2		1		12		24	39		2		1		12		24	39
Rabbi trust investments
Cash equivalents	5		—		—		—	5		77		—		—		—	77
Mutual funds	23		—		—		—	23		58		—		—		—	58
Fixed income	—		—		—		—	—		—		12		—		—	12
Life insurance contracts	—		22		—		—	22		—		71		22		—	93
Rabbi trust investments subtotal	28		22		—		—	50		135		83		22		—	240
Commodity derivative assets
Economic hedges	557		2,378		1,290		—	4,225		557		2,378		1,290		—	4,225
Proprietary trading	2		31		35		—	68		2		31		35		—	68
Effect of netting and allocation of collateral(e)(f)	(585	)	(1,769	)	(635	)	—	(2,989	)	(585	)	(1,769	)	(635	)	—	(2,989	)
Commodity derivative assets subtotal	(26	)	640		690		—	1,304		(26	)	640		690		—	1,304

	Generation														Exelon
As of December 31, 2017	Level 1			Level 2			Level 3			Not subject to leveling		Total			Level 1			Level 2			Level 3			Not subject to leveling		Total
Interest rate and foreign currency derivative assets
Derivatives designated as hedging instruments	—			3			—			—		3			—			6			—			—		6
Economic hedges	—			10			—			—		10			—			10			—			—		10
Effect of netting and allocation of collateral	(2		)	(5		)	—			—		(7		)	(2		)	(5		)	—			—		(7		)
Interest rate and foreign currency derivative assets subtotal	(2		)	8			—			—		6			(2		)	11			—			—		9
Other investments	—			—			37			—		37			—			—			37			—		37
Total assets	6,385			3,729			1,387			3,534		15,035			6,980			3,793			1,409			3,534		15,716
Liabilities
Commodity derivative liabilities
Economic hedges	(712		)	(2,226		)	(845		)	—		(3,783		)	(713		)	(2,226		)	(1,101		)	—		(4,040		)
Proprietary trading	(2		)	(42		)	(9		)	—		(53		)	(2		)	(42		)	(9		)	—		(53		)
Effect of netting and allocation of collateral(e)(f)	650			2,089			716			—		3,455			651			2,089			716			—		3,456
Commodity derivative liabilities subtotal	(64		)	(179		)	(138		)	—		(381		)	(64		)	(179		)	(394		)	—		(637		)
Interest rate and foreign currency derivative liabilities
Derivatives designated as hedging instruments	—			(2		)	—			—		(2		)	—			(2		)	—			—		(2		)
Economic hedges	(1		)	(8		)	—			—		(9		)	(1		)	(8		)	—			—		(9		)
Effect of netting and allocation of collateral	2			5			—			—		7			2			5			—			—		7
Interest rate and foreign currency derivative liabilities subtotal	1			(5		)	—			—		(4		)	1			(5		)	—			—		(4		)
Deferred compensation obligation	—			(38		)	—			—		(38		)	—			(145		)	—			—		(145		)
Total liabilities	(63		)	(222		)	(138		)	—		(423		)	(63		)	(329		)	(394		)	—		(786		)
Total net assets	$	6,322		$	3,507		$	1,249		$	3,534	$	14,612		$	6,917		$	3,464		$	1,015		$	3,534	$	14,930

	Generation										Exelon
As of December 31, 2016	Level 1		Level 2		Level 3		Not subject to leveling		Total		Level 1		Level 2		Level 3		Not subject to leveling		Total
Assets
Cash equivalents(a)	$	39	$	—	$	—	$	—	$	39	$	373	$	—	$	—	$	—	$	373
NDT fund investments

	Generation									Exelon
As of December 31, 2016	Level 1		Level 2		Level 3		Not subject to leveling	Total		Level 1		Level 2		Level 3		Not subject to leveling	Total
Cash equivalents(b)	110		19		—		—	129		110		19		—		—	129
Equities	3,551		452		—		2,011	6,014		3,551		452		—		2,011	6,014
Fixed income
Corporate debt	—		1,554		250		—	1,804		—		1,554		250		—	1,804
U.S. Treasury and agencies	1,291		29		—		—	1,320		1,291		29		—		—	1,320
Foreign governments	—		37		—		—	37		—		37		—		—	37
State and municipal debt	—		264		—		—	264		—		264		—		—	264
Other(c)	—		59		—		493	552		—		59		—		493	552
Fixed income subtotal	1,291		1,943		250		493	3,977		1,291		1,943		250		493	3,977
Middle market lending	—		—		427		71	498		—		—		427		71	498
Private equity	—		—		—		148	148		—		—		—		148	148
Real estate	—		—		—		326	326		—		—		—		326	326
NDT fund investments subtotal(d)	4,952		2,414		677		3,049	11,092		4,952		2,414		677		3,049	11,092
Pledged assets for Zion Station decommissioning
Cash equivalents	11		—		—		—	11		11		—		—		—	11
Equities	—		2		—		—	2		—		2		—		—	2
Fixed Income - U.S. Treasury and agencies	16		1		—		—	17		16		1		—		—	17
Middle market lending	—		—		19		64	83		—		—		19		64	83
Pledged assets for Zion Station decommissioning subtotal	27		3		19		64	113		27		3		19		64	113
Rabbi trust investments
Cash equivalents	2		—		—		—	2		74		—		—		—	74
Mutual funds	19		—		—		—	19		50		—		—		—	50
Fixed income	—		—		—		—	—		—		16		—		—	16
Life insurance contracts	—		18		—		—	18		—		64		20		—	84
Rabbi trust investments subtotal	21		18		—		—	39		124		80		20		—	224
Commodity derivative assets
Economic hedges	1,356		2,505		1,229		—	5,090		1,358		2,505		1,229		—	5,092
Proprietary trading	3		50		23		—	76		3		50		23		—	76
Effect of netting and allocation of collateral(e)(f)	(1,162	)	(2,142	)	(481	)	—	(3,785	)	(1,164	)	(2,142	)	(481	)	—	(3,787	)
Commodity derivative assets subtotal	197		413		771		—	1,381		197		413		771		—	1,381

	Generation														Exelon
As of December 31, 2016	Level 1			Level 2			Level 3			Not subject to leveling		Total			Level 1			Level 2			Level 3			Not subject to leveling		Total
Interest rate and foreign currency derivative assets
Derivatives designated as hedging instruments	—			—			—			—		—			—			16			—			—		16
Economic hedges	—			28			—			—		28			—			28			—			—		28
Proprietary trading	3			2			—			—		5			3			2			—			—		5
Effect of netting and allocation of collateral	(2		)	(19		)	—			—		(21		)	(2		)	(19		)	—			—		(21		)
Interest rate and foreign currency derivative assets subtotal	1			11			—			—		12			1			27			—			—		28
Other investments	—			—			42			—		42			—			—			42			—		42
Total assets	5,237			2,859			1,509			3,113		12,718			5,674			2,937			1,529			3,113		13,253
Liabilities
Commodity derivative liabilities
Economic hedges	(1,267		)	(2,378		)	(794		)	—		(4,439		)	(1,267		)	(2,378		)	(1,052		)	—		(4,697		)
Proprietary trading	(3		)	(50		)	(26		)	—		(79		)	(3		)	(50		)	(26		)	—		(79		)
Effect of netting and allocation of collateral(e)(f)	1,233			2,339			542			—		4,114			1,233			2,339			542			—		4,114
Commodity derivative liabilities subtotal	(37		)	(89		)	(278		)	—		(404		)	(37		)	(89		)	(536		)	—		(662		)
Interest rate and foreign currency derivative liabilities
Derivatives designated as hedging instruments	—			(10		)	—			—		(10		)	—			(10		)	—			—		(10		)
Economic hedges	—			(21		)	—			—		(21		)	—			(21		)	—			—		(21		)
Proprietary trading	(4		)	—			—			—		(4		)	(4		)	—			—			—		(4		)
Effect of netting and allocation of collateral	4			19			—			—		23			4			19			—			—		23
Interest rate and foreign currency derivative liabilities subtotal	—			(12		)	—			—		(12		)	—			(12		)	—			—		(12		)
Deferred compensation obligation	—			(34		)	—			—		(34		)	—			(136		)	—			—		(136		)
Total liabilities	(37		)	(135		)	(278		)	—		(450		)	(37		)	(237		)	(536		)	—		(810		)
Total net assets	$	5,200		$	2,724		$	1,231		$	3,113	$	12,268		$	5,637		$	2,700		$	993		$	3,113	$	12,443

__________

(a) Generation excludes cash of $259 million and $252 million at December 31, 2017 and 2016 and restricted cash of $127 million and $157 million at December 31, 2017 and 2016.  Exelon excludes cash of $389 million and $360 million at December 31, 2017 and 2016 and restricted cash of $145 million and $180 million at December 31, 2017 and 2016 and includes long-term restricted cash of $85 million and $25 million at December 31, 2017 and 2016, which is reported in Other deferred debits on the Consolidated Balance Sheets.

(b) Includes $77 million and $29 million of cash received from outstanding repurchase agreements at December 31, 2017 and 2016, respectively, and is offset by an obligation to repay upon settlement of the agreement as discussed in (d) below.

(c) Includes derivative instruments of less than $1 million and $(2) million, which have a total notional amount of $811 million and $933 million at December 31, 2017 and 2016, respectively. The notional principal amounts for these instruments provide one measure of the transaction volume outstanding as of the fiscal years ended and do not represent the amount of the company's exposure to credit or market loss.

(d) Excludes net liabilities of $82 million and $31 million at December 31, 2017 and 2016, respectively. These items consist of receivables related to pending securities sales, interest and dividend receivables, repurchase agreement obligations, and payables related to pending securities purchases. The repurchase agreements are generally short-term in nature with durations generally of 30 days or less.

(e) Collateral posted/(received) from counterparties totaled $65 million, $320 million and $81 million allocated to Level 1, Level 2 and Level 3 mark-to-market derivatives, respectively, as of December 31, 2017. Collateral posted/(received) from counterparties totaled $71 million, $197 million and $61 million allocated to Level 1, Level 2 and Level 3 mark-to-market derivatives, respectively, as of December 31, 2016.

Fair Value Assets And Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Text Block]

The following tables present the fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis during the years ended December 31, 2017 and 2016:

																					Successor
	Generation																ComEd				PHI						Exelon
For the year ended December 31, 2017	NDT Fund Investments			Pledged Assets for Zion Station Decommissioning			Mark-to-Market Derivatives				Other Investments			Total Generation			Mark-to-Market Derivatives				Life Insurance Contracts			Eliminated in Consolidation			Total
Balance as of January 1, 2017	$	677		$	19		$	493			$	42		$	1,231		$	(258	)		$	20		$	—		$	993
Total realized / unrealized gains (losses)
Included in net income	3			—			(90		)	(a)	3			(84		)	—				3			—			(81		)
Included in noncurrent payables to affiliates	6			—			—				—			6			—				—			(6		)	—
Included in payable for Zion Station decommissioning	—			(8		)	—				—			(8		)	—				—			—			(8		)
Included in regulatory assets/liabilities	—			—			—				—			—			2			(b)	—			6			8
Change in collateral	—			—			20				—			20			—				—			—			20
Purchases, sales, issuances and settlements
Purchases	64			1			178				5			248			—				—			—			248
Sales	—			—			(16		)		—			(16		)	—				—			—			(16		)
Issuances	—			—			—				—			—			—				(1		)	—			(1		)
Settlements	(102		)	—			(8		)	(c)	—			(110		)	—				—			—			(110		)
Transfers into Level 3	—			—			(6		)		—			(6		)	—				—			—			(6		)
Transfers out of Level 3	—			—			(50		)		(11		)	(61		)	—				—			—			(61		)
Other miscellaneous	—			—			31			(d)	(2		)	29			—				—			—			29
Balance as of December 31, 2017	$	648		$	12		$	552			$	37		$	1,249		$	(256	)		$	22		$	—		$	1,015
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities as of December 31, 2017	$	1		$	—		$	254			$	3		$	258		$	—			$	3		$	—		$	261

																				Successor
	Generation															ComEd				PHI(f)						Exelon
For the year ended December 31, 2016	NDT Fund Investments			Pledged Assets for Zion Station Decommissioning			Mark-to-Market Derivatives				Other Investments		Total Generation			Mark-to-Market Derivatives				Life Insurance Contracts			Eliminated in Consolidation			Total
Balance as of January 1, 2016	$	670		$	22		$	1,051			$	33	$	1,776		$	(247	)		$	—		$	—		$	1,529
Included due to merger	—			—			—				—		—			—				20			—			20
Total realized / unrealized gains (losses)
Included in net income	7			—			(568		)	(a)	1		(560		)	—				3			—			(557		)
Included in noncurrent payables to affiliates	16			—			—				—		16			—				—			(16		)	—
Included in regulatory assets/liabilities	—			—			—				—		—			(11		)	(b)	—			16			5
Change in collateral	—			—			(141		)		—		(141		)	—				—			—			(141		)
Purchases, sales, issuances and settlements
Purchases	143			2			342			(e)	7		494			—				—			—			494
Sales	(1		)	(5		)	(9		)		—		(15		)	—				—			—			(15		)
Issuances	—			—			—				—		—			—				(3		)	—			(3		)
Settlements	(144		)	—			—				—		(144		)	—				—			—			(144		)
Transfers into Level 3	—			—			1				1		2			—				—			—			2
Transfers out of Level 3	(14		)	—			(183		)		—		(197		)	—				—			—			(197		)
Balance as of December 31, 2016	$	677		$	19		$	493			$	42	$	1,231		$	(258	)		$	20		$	—		$	993
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities held as of December 31, 2016	$	5		$	—		$	109			$	—	$	114		$	—			$	2		$	—		$	116

__________

(a) Includes a reduction for the reclassification of $352 million and $677 million of realized gains due to the settlement of derivative contracts for the years ended December 31, 2017 and 2016, respectively.

(b) Includes $18 million of decreases in fair value and an increase for realized losses due to settlements of $20 million recorded in purchased power expense associated with floating-to-fixed energy swap contracts with unaffiliated suppliers for the year ended December 31, 2017. Includes $29 million of decreases in fair value and an increase for realized losses due to settlements of $18 million recorded in purchased power expense associated with floating-to-fixed energy swap contracts with unaffiliated suppliers for the year ended December 31, 2016.

(c) Exelon includes the settlement value for any open contracts that were net settled prior to their scheduled maturity within this line item.

(d) As a result of the bankruptcy filing for EGTP on November 7, 2017, the net mark-to-market commodity contracts were deconsolidated from Exelon's and Generation's consolidated financial statements.

(e) Includes $168 million of fair value from contracts acquired as a result of portfolio acquisitions.

(f) Successor period represents activity from March 24, 2016 to December 31, 2016. See tables below for PHI's predecessor periods, as well as activity for Pepco for the years ended December 31, 2017 and 2016.

	Predecessor
	January 1, 2016 to March 23, 2016
PHI	Preferred Stock			Life Insurance Contracts
Beginning Balance	$	18		$	19
Total realized / unrealized (losses) gains
Included in net income	(18		)	1
Ending Balance	$	—		$	20
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities for the period	$	—		$	1

	Life Insurance Contracts
	For the year ended December 31,
Pepco	2017			2016
Balance as of January 1	$	20		$	19
Total realized / unrealized gains (losses)
Included in net income	3			3
Purchases, sales, issuances and settlements
Issuances	(1		)	(3		)
Balance as of December 31	$	22		$	19
The amount of total gains (losses) included in income attributed to the change in unrealized gains (losses) related to assets and liabilities for the period	$	3		$	3

Total realized and unrealized gains (losses) included in income for Level 3 assets and liabilities measured at fair value on a recurring basis

The following tables present the income statement classification of the total realized and unrealized gains (losses) included in income for Level 3 assets and liabilities measured at fair value on a recurring basis during the years ended December 31, 2017 and 2016:

								Successor
	Generation							PHI		Exelon
	Operating Revenues		Purchased Power and Fuel			Other, net(a)		Operating and Maintenance		Operating Revenues		Purchased Power and Fuel			Operating and Maintenance		Other, net(a)
Total gains (losses) included in net income for the year ended December 31, 2017	$	28	$	(126	)	$	6	$	3	$	28	$	(126	)	$	3	$	6
Change in the unrealized gains (losses) relating to assets and liabilities held for the year ended December 31, 2017	290		(36		)	4		3		290		(36		)	3		4

									Successor
	Generation								PHI(b)		Exelon
	Operating Revenues			Purchased Power and Fuel			Other, net(a)		Other, net(a)		Operating Revenues			Purchased Power and Fuel			Other, net(a)
Total gains (losses) included in net income for the year ended December 31, 2016	$	(477	)	$	(91	)	$	7	$	3	$	(477	)	$	(91	)	$	10
Change in the unrealized gains (losses) relating to assets and liabilities held for the year ended December 31, 2016	154			(45		)	5		2		154			(45		)	7

	Predecessor
	PHI			Pepco
	January 1, 2016 to March 23, 2016			December 31, 2017		December 31, 2017		December 31, 2016
	Other, net(a)			Operating and Maintenance		Other, net(a)
Total (losses) gains included in net income	$	(17	)	$	3	$	—	$	3
Change in the unrealized gains (losses) relating to assets and liabilities held	1			3		—		3

__________

(a) Other, net activity consists of realized and unrealized gains (losses) included in income for the NDT funds held by Generation, accrued interest on a convertible promissory note at Generation and the life insurance contracts held by PHI and Pepco.

(b) Successor period represents activity from March 24, 2016 to December 31, 2016. See the subsequent table for PHI's predecessor periods, as well as activity for Pepco for the year ended December 31, 2017 and 2016.

Fair value reconciliation of Level 3 assets and liabilities measured at fair value on a recurring basis, valuation technique

The following tables present the significant inputs to the forward curve used to value these positions:

Type of trade	Fair Value at December 31, 2017			Valuation Technique	Unobservable Input	Range
Mark-to-market derivatives—Economic hedges (Exelon and Generation)(a)(b)	$	445		Discounted Cash Flow	Forward power price	$3	-	$124
					Forward gas price	$1.27	-	$12.80
				Option Model	Volatility percentage	11%	-	139%
Mark-to-market derivatives—Proprietary trading (Exelon and Generation)(a)(b)	$	26		Discounted Cash Flow	Forward power price	$14	-	$94
Mark-to-market derivatives (Exelon and ComEd)	$	(256	)	Discounted Cash Flow	Forward heat rate(c)	9x	-	10x
					Marketability reserve	4%	-	8%
					Renewable factor	88%	-	120%

______

(a) The valuation techniques, unobservable inputs and ranges are the same for the asset and liability positions.

(b) The fair values do not include cash collateral posted on level three positions of $81 million as of December 31, 2017.

(c) Quoted forward natural gas rates are utilized to project the forward power curve for the delivery of energy at specified future dates. The natural gas curve is extrapolated beyond its observable period to the end of the contract’s delivery.

Type of trade	Fair Value at December 31, 2016			Valuation Technique	Unobservable Input	Range
Mark-to-market derivatives—Economic hedges (Exelon and Generation)(a)(b)	$	435		Discounted Cash Flow	Forward power price	$11	-	$130
					Forward gas price	$1.72	-	$9.20
				Option Model	Volatility percentage	8%	-	173%
Mark-to-market derivatives— Proprietary trading (Exelon and Generation)(a)(b)	$	(3	)	Discounted Cash Flow	Forward power price	$19	-	$79
Mark-to-market derivatives (Exelon and ComEd)	$	(258	)	Discounted Cash Flow	Forward heat rate(c)	8x	-	9x
					Marketability reserve	3%	-	8%
					Renewable factor	89%	-	121%

__________

(a) The valuation techniques, unobservable inputs and ranges are the same for the asset and liability positions.

(b) The fair values do not include cash collateral posted on level three positions of $61 million as of December 31, 2016