Consolidated Statement Of Cash Flow (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
OPERATING ACTIVITIES
Net income	$ 130	$ 158
Income from discontinued operations	0	(1)
Adjustments to reconcile net income (loss) to net cash from operating activities:
Depreciation and amortization	221	210
Non-cash rents from cross-border energy lease investments	(26)	(28)
Gain on early termination of finance leases held in trust		(39)
Deferred income taxes	235	61
Net unrealized (gains) losses on derivatives	(12)	7
Impairment losses	3
Other	(8)	(10)
Changes in:
Accounts receivable	60	63
Inventories	(17)	(4)
Prepaid expenses	(36)	(34)
Regulatory assets and liabilities, net	(93)	(40)
Accounts payable and accrued liabilities	(45)	(71)
Pension contributions	(200)	(110)
Prepaid pension expense	33	26
Cash collateral related to derivative activities	53	44
Income tax-related prepayments, receivables and payables	(184)	34
Other assets and liabilities	10	26
Conectiv Energy net assets held for sale		42
Net Cash (Used By) From Operating Activities	124	334
INVESTING ACTIVITIES
Investment in property, plant and equipment	(589)	(387)
Department of Energy capital reimbursement awards received	22	16
Proceeds from early termination of finance leases held in trust		161
Changes in restricted cash equivalents	2	(3)
Net other investing activities	5	(7)
Net Cash (Used By) From Investing Activities	(560)	(220)
FINANCING ACTIVITIES
Dividends paid on common stock	(123)	(122)
Common stock issued for the Dividend Reinvestment Plan and employee-related compensation	28	25
Redemption of preferred stock		(6)
Issuances of long-term debt	450	235
Reacquisitions of long-term debt	(122)	(52)
Issuances (Repayments) of short-term debt, net	143	(139)
Cost of issuances	(7)	(2)
Net other financing activities	(3)	(16)
Net Cash (Used By) From Financing Activities	366	(77)
Net Decrease in Cash and Cash Equivalents	(70)	37
Cash and Cash Equivalents at Beginning of Period	109	21
CASH AND CASH EQUIVALENTS AT END OF PERIOD	39	58
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash (received) paid for income taxes	(3)	(2)
Potomac Electric Power Co [Member]
OPERATING ACTIVITIES
Net income	51	50
Adjustments to reconcile net income (loss) to net cash from operating activities:
Depreciation and amortization	95	84
Deferred income taxes	127	17
Changes in:
Accounts receivable	4	(9)
Inventories	(11)
Prepaid expenses	14	14
Regulatory assets and liabilities, net	(34)	(1)
Accounts payable and accrued liabilities	(2)	(8)
Pension contributions	(85)	(40)
Prepaid pension expense	11	9
Income tax-related prepayments, receivables and payables	(129)	62
Other assets and liabilities	(5)	(6)
Net Cash (Used By) From Operating Activities	36	172
INVESTING ACTIVITIES
Investment in property, plant and equipment	(306)	(205)
Department of Energy capital reimbursement awards received	21	14
Net other investing activities	3	(6)
Net Cash (Used By) From Investing Activities	(282)	(197)
FINANCING ACTIVITIES
Capital contribution from Parent	50
Issuances of long-term debt	200
Reacquisitions of long-term debt	(38)
Issuances (Repayments) of short-term debt, net	34
Cost of issuances	(4)
Net other financing activities	(1)	(5)
Net Cash (Used By) From Financing Activities	241	(5)
Net Decrease in Cash and Cash Equivalents	(5)	(30)
Cash and Cash Equivalents at Beginning of Period	12	88
CASH AND CASH EQUIVALENTS AT END OF PERIOD	7	58
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash (received) paid for income taxes	1	(71)
Delmarva Power & Light Co/De [Member]
OPERATING ACTIVITIES
Net income	34	45
Adjustments to reconcile net income (loss) to net cash from operating activities:
Depreciation and amortization	49	44
Deferred income taxes	33	40
Changes in:
Accounts receivable	25	28
Inventories	(6)	1
Regulatory assets and liabilities, net	(23)	(5)
Accounts payable and accrued liabilities	6	(24)
Pension contributions	(85)	(40)
Income tax-related prepayments, receivables and payables	(12)	(25)
Other assets and liabilities	12	17
Net Cash (Used By) From Operating Activities	33	81
INVESTING ACTIVITIES
Investment in property, plant and equipment	(145)	(99)
Net other investing activities	(2)	(1)
Net Cash (Used By) From Investing Activities	(147)	(100)
FINANCING ACTIVITIES
Issuances of long-term debt	250	35
Reacquisitions of long-term debt	(66)	(35)
Issuances (Repayments) of short-term debt, net	(47)
Cost of issuances	(3)
Net Cash (Used By) From Financing Activities	134
Net Decrease in Cash and Cash Equivalents	20	(19)
Cash and Cash Equivalents at Beginning of Period	5	69
CASH AND CASH EQUIVALENTS AT END OF PERIOD	25	50
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash (received) paid for income taxes	(3)	8
Atlantic City Electric Co [Member]
OPERATING ACTIVITIES
Net income	16	24
Adjustments to reconcile net income (loss) to net cash from operating activities:
Depreciation and amortization	55	66
Deferred income taxes	64	30
Changes in:
Prepaid expenses	(43)	(56)
Regulatory assets and liabilities, net	(36)	(34)
Accounts payable and accrued liabilities	5	(5)
Pension contributions	(30)	(30)
Income tax-related prepayments, receivables and payables	(47)	13
Other assets and liabilities	(3)	11
Net Cash (Used By) From Operating Activities	(19)	19
INVESTING ACTIVITIES
Investment in property, plant and equipment	(114)	(60)
Department of Energy capital reimbursement awards received	1	2
Net other investing activities	2	(3)
Net Cash (Used By) From Investing Activities	(111)	(61)
FINANCING ACTIVITIES
Dividends paid on common stock	(15)
Redemption of preferred stock		(6)
Issuances of long-term debt		200
Reacquisitions of long-term debt	(18)	(17)
Issuances (Repayments) of short-term debt, net	74	(133)
Net other financing activities	1	(2)
Net Cash (Used By) From Financing Activities	42	42
Net Decrease in Cash and Cash Equivalents	(88)
Cash and Cash Equivalents at Beginning of Period	91	4
CASH AND CASH EQUIVALENTS AT END OF PERIOD	3	4
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash (received) paid for income taxes		$ (18)