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Supplemental Financial Information Supplemental Financial Information - Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Mar. 24, 2016 | Mar. 23, 2016 | Dec. 31, 2015
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Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | $ 1,349 | $ 898 | $ 635 |  |  | $ 6,502
Restricted cash |  | 247 | 207 | 253 |  |  | 205
Restricted cash included in other long-term assets |  | 185 | 85 | 26 |  |  | 5
Total cash, cash equivalents and restricted cash |  | 1,781 | 1,190 | 914 |  |  | 6,712
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 1,656 | 1,858 |  |  |  |
Allowance for uncollectible accounts | [2] | (319) | (322) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 313 | 298 |  |  |  |
Allowance for uncollectible accounts | [3] | (34) | (31) |  |  |  |
Purchased receivables, net |  | 279 | 267 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 267 | 297 |  |  |  |
Equity investments without readily determinable fair values |  | 72 | 62 |  |  |  |
Other Investments |  | 2 |  |  |  |  |
Total Investments |  | 625 | 640 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 1,191 | 978 |  |  |  |
Taxes accrued |  | 412 | 373 |  |  |  |
Interest accrued |  | 334 | 328 |  |  |  |
Severance accrued |  | 44 | 58 |  |  |  |
Other accrued expenses |  | 131 | 100 |  |  |  |
Total accrued expenses |  | 2,112 | 1,837 |  |  |  |
Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 14 | 14 |  |  |  |
Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 180 | 206 |  |  |  |
NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 70 | 76 |  |  |  |
Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 3 | 1 |  |  |  |
Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 244 | 244 |  |  |  |
Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 40 | 37 |  |  |  |
Exelon Generation Co L L C [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 750 | 416 | 290 |  |  | 431
Restricted cash |  | 153 | 138 | 158 |  |  | 123
Restricted cash included in other long-term assets |  | 0 | 0 | 0 |  |  | 2
Total cash, cash equivalents and restricted cash |  | 903 | 554 | 448 |  |  | 556
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 965 | 1,017 |  |  |  |
Allowance for uncollectible accounts | [2] | (104) | (114) |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 251 | 283 |  |  |  |
Equity investments without readily determinable fair values |  | 72 | 62 |  |  |  |
Other Investments |  | 2 |  |  |  |  |
Total Investments |  | 414 | 433 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 479 | 407 |  |  |  |
Taxes accrued |  | 226 | 444 |  |  |  |
Interest accrued |  | 77 | 78 |  |  |  |
Severance accrued |  | 26 | 30 |  |  |  |
Other accrued expenses |  | 90 | 63 |  |  |  |
Total accrued expenses |  | 898 | 1,022 |  |  |  |
Exelon Generation Co L L C [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 0 | 0 |  |  |  |
Exelon Generation Co L L C [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 180 | 206 |  |  |  |
Exelon Generation Co L L C [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 70 | 76 |  |  |  |
Exelon Generation Co L L C [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 1 | 1 |  |  |  |
Exelon Generation Co L L C [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 49 | 51 |  |  |  |
Exelon Generation Co L L C [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 40 | 37 |  |  |  |
Commonwealth Edison Co [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 135 | 76 | 56 |  |  | 67
Restricted cash |  | 29 | 5 | 2 |  |  | 2
Restricted cash included in other long-term assets |  | 166 | 63 | 0 |  |  | 0
Total cash, cash equivalents and restricted cash |  | 330 | 144 | 58 |  |  | 69
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 223 | 242 |  |  |  |
Allowance for uncollectible accounts | [2] | (81) | (73) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 94 | 87 |  |  |  |
Allowance for uncollectible accounts | [3] | (17) | (14) |  |  |  |
Purchased receivables, net |  | 77 | 73 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 6 | 6 |  |  |  |
Equity investments without readily determinable fair values |  | 0 | 0 |  |  |  |
Other Investments |  | 0 |  |  |  |  |
Total Investments |  | 6 | 6 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 187 | 158 |  |  |  |
Taxes accrued |  | 71 | 60 |  |  |  |
Interest accrued |  | 105 | 102 |  |  |  |
Severance accrued |  | 2 | 2 |  |  |  |
Other accrued expenses |  | 8 | 5 |  |  |  |
Total accrued expenses |  | 373 | 327 |  |  |  |
Commonwealth Edison Co [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 6 | 6 |  |  |  |
Commonwealth Edison Co [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Commonwealth Edison Co [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Commonwealth Edison Co [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Commonwealth Edison Co [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 0 | 0 |  |  |  |
Commonwealth Edison Co [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 0 | 0 |  |  |  |
PECO Energy Co [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 130 | 271 | 63 |  |  | 295
Restricted cash |  | 5 | 4 | 4 |  |  | 3
Restricted cash included in other long-term assets |  | 0 | 0 | 0 |  |  | 0
Total cash, cash equivalents and restricted cash |  | 135 | 275 | 67 |  |  | 298
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 114 | 162 |  |  |  |
Allowance for uncollectible accounts | [2] | (61) | (56) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 74 | 70 |  |  |  |
Allowance for uncollectible accounts | [3] | (5) | (5) |  |  |  |
Purchased receivables, net |  | 69 | 65 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 8 | 8 |  |  |  |
Equity investments without readily determinable fair values |  | 0 | 0 |  |  |  |
Other Investments |  | 0 |  |  |  |  |
Total Investments |  | 25 | 25 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 49 | 64 |  |  |  |
Taxes accrued |  | 28 | 15 |  |  |  |
Interest accrued |  | 33 | 33 |  |  |  |
Severance accrued |  | 0 | 0 |  |  |  |
Other accrued expenses |  | 3 | 2 |  |  |  |
Total accrued expenses |  | 113 | 114 |  |  |  |
PECO Energy Co [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 8 | 8 |  |  |  |
PECO Energy Co [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
PECO Energy Co [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
PECO Energy Co [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
PECO Energy Co [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 17 | 17 |  |  |  |
PECO Energy Co [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 0 | 0 |  |  |  |
Baltimore Gas and Electric Company [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 7 | 17 | 23 |  |  | 9
Restricted cash |  | 6 | 1 | 24 |  |  | 24
Restricted cash included in other long-term assets |  | 0 | 0 | 3 |  |  | 3
Total cash, cash equivalents and restricted cash |  | 13 | 18 | 50 |  |  | 36
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 168 | 205 |  |  |  |
Allowance for uncollectible accounts | [2] | (20) | (24) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 61 | 58 |  |  |  |
Allowance for uncollectible accounts | [3] | (3) | (3) |  |  |  |
Purchased receivables, net |  | 58 | 55 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 0 | 0 |  |  |  |
Equity investments without readily determinable fair values |  | 0 | 0 |  |  |  |
Other Investments |  | 0 |  |  |  |  |
Total Investments |  | 5 | 5 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 68 | 58 |  |  |  |
Taxes accrued |  | 46 | 71 |  |  |  |
Interest accrued |  | 39 | 34 |  |  |  |
Severance accrued |  | 0 | 0 |  |  |  |
Other accrued expenses |  | 2 | 1 |  |  |  |
Total accrued expenses |  | 155 | 164 |  |  |  |
Baltimore Gas and Electric Company [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 0 | 0 |  |  |  |
Baltimore Gas and Electric Company [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Baltimore Gas and Electric Company [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Baltimore Gas and Electric Company [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Baltimore Gas and Electric Company [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 5 | 5 |  |  |  |
Baltimore Gas and Electric Company [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 0 | 0 |  |  |  |
Pepco Holdings LLC [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 124 | 30 |  |  |  |
Restricted cash |  | 43 | 42 |  |  |  |
Restricted cash included in other long-term assets |  | 19 | 23 |  |  |  |
Total cash, cash equivalents and restricted cash |  | 186 | 95 | 236 |  |  |
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 186 | 232 |  |  |  |
Allowance for uncollectible accounts | [2] | (53) | (55) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 84 | 83 |  |  |  |
Allowance for uncollectible accounts | [3] | (9) | (9) |  |  |  |
Purchased receivables, net |  | 75 | 74 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 0 | 0 |  |  |  |
Equity investments without readily determinable fair values |  | 0 | 0 |  |  |  |
Other Investments |  | 0 |  |  |  |  |
Total Investments |  | 130 | 132 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 99 | 106 |  |  |  |
Taxes accrued |  | 74 | 61 |  |  |  |
Interest accrued |  | 50 | 48 |  |  |  |
Severance accrued |  | 5 | 17 |  |  |  |
Other accrued expenses |  | 28 | 29 |  |  |  |
Total accrued expenses |  | 256 | 261 |  |  |  |
Pepco Holdings LLC [Member] | Successor [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  |  |  | 170 |  |  |
Restricted cash |  |  |  | 43 |  |  |
Restricted cash included in other long-term assets |  |  |  | 23 |  |  |
Total cash, cash equivalents and restricted cash |  |  |  | 236 | $ 348 |  |
Pepco Holdings LLC [Member] | Predecessor [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  |  |  |  |  | $ 319 | 26
Restricted cash |  |  |  |  |  | 11 | 14
Restricted cash included in other long-term assets |  |  |  |  |  | 18 | 18
Total cash, cash equivalents and restricted cash |  |  |  |  |  | $ 348 | 58
Pepco Holdings LLC [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 0 | 0 |  |  |  |
Pepco Holdings LLC [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Pepco Holdings LLC [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Pepco Holdings LLC [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Pepco Holdings LLC [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 130 | 132 |  |  |  |
Pepco Holdings LLC [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 0 | 0 |  |  |  |
Potomac Electric Power Company [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 16 | 5 | 9 |  |  | 5
Restricted cash |  | 37 | 35 | 33 |  |  | 2
Restricted cash included in other long-term assets |  | 0 | 0 | 0 |  |  | 0
Total cash, cash equivalents and restricted cash |  | 53 | 40 | 42 |  |  | 7
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 97 | 133 |  |  |  |
Allowance for uncollectible accounts | [2] | (21) | (21) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 57 | 56 |  |  |  |
Allowance for uncollectible accounts | [3] | (5) | (5) |  |  |  |
Purchased receivables, net |  | 52 | 51 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 0 | 0 |  |  |  |
Equity investments without readily determinable fair values |  | 0 | 0 |  |  |  |
Other Investments |  | 0 |  |  |  |  |
Total Investments |  | 105 | 102 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 29 | 29 |  |  |  |
Taxes accrued |  | 58 | 68 |  |  |  |
Interest accrued |  | 25 | 23 |  |  |  |
Severance accrued |  | 0 | 0 |  |  |  |
Other accrued expenses |  | 14 | 17 |  |  |  |
Total accrued expenses |  | 126 | 137 |  |  |  |
Potomac Electric Power Company [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 0 | 0 |  |  |  |
Potomac Electric Power Company [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Potomac Electric Power Company [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Potomac Electric Power Company [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Potomac Electric Power Company [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 105 | 102 |  |  |  |
Potomac Electric Power Company [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 0 | 0 |  |  |  |
Delmarva Power & Light Company [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 23 | 2 | 46 |  |  | 5
Restricted cash |  | 1 | 0 | 0 |  |  | 0
Restricted cash included in other long-term assets |  | 0 | 0 | 0 |  |  | 0
Total cash, cash equivalents and restricted cash |  | 24 | 2 | 46 |  |  | 5
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 59 | 68 |  |  |  |
Allowance for uncollectible accounts | [2] | (13) | (16) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 8 | 9 |  |  |  |
Allowance for uncollectible accounts | [3] | (1) | (1) |  |  |  |
Purchased receivables, net |  | 7 | 8 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 0 | 0 |  |  |  |
Equity investments without readily determinable fair values |  | 0 | 0 |  |  |  |
Other Investments |  | 0 |  |  |  |  |
Total Investments |  | 0 | 0 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 19 | 17 |  |  |  |
Taxes accrued |  | 4 | 4 |  |  |  |
Interest accrued |  | 8 | 8 |  |  |  |
Severance accrued |  | 0 | 0 |  |  |  |
Other accrued expenses |  | 8 | 6 |  |  |  |
Total accrued expenses |  | 39 | 35 |  |  |  |
Delmarva Power & Light Company [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 0 | 0 |  |  |  |
Delmarva Power & Light Company [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Delmarva Power & Light Company [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Delmarva Power & Light Company [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Delmarva Power & Light Company [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 0 | 0 |  |  |  |
Delmarva Power & Light Company [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | 0 | 0 |  |  |  |
Atlantic City Electric Company [Member] |  |  |  |  |  |  |
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract] |  |  |  |  |  |  |
Cash and cash equivalents |  | 7 | 2 | 101 |  |  | 3
Restricted cash |  | 4 | 6 | 9 |  |  | 12
Restricted cash included in other long-term assets |  | 19 | 23 | 23 |  |  | 18
Total cash, cash equivalents and restricted cash |  | 30 | 31 | $ 133 |  |  | $ 33
Contracts Receivable [Abstract] |  |  |  |  |  |  |
Unbilled customer revenues | [1] | 30 | 31 |  |  |  |
Allowance for uncollectible accounts | [2] | (19) | (18) |  |  |  |
Purchased Receivables [Abstract] |  |  |  |  |  |  |
Purchased receivables |  | 19 | 18 |  |  |  |
Allowance for uncollectible accounts | [3] | (3) | (3) |  |  |  |
Purchased receivables, net |  | 16 | 15 |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Total equity method investments |  | 0 | 0 |  |  |  |
Equity investments without readily determinable fair values |  | 0 | 0 |  |  |  |
Other Investments |  | 0 |  |  |  |  |
Total Investments |  | 0 | 0 |  |  |  |
Accrued Expenses [Abstract] |  |  |  |  |  |  |
Compensation-related accruals | [4] | 12 | 11 |  |  |  |
Taxes accrued |  | 5 | 5 |  |  |  |
Interest accrued |  | 12 | 12 |  |  |  |
Severance accrued |  | 0 | 0 |  |  |  |
Other accrued expenses |  | 6 | 5 |  |  |  |
Total accrued expenses |  | 35 | 33 |  |  |  |
Atlantic City Electric Company [Member] | Financing Trusts |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments | [5] | 0 | 0 |  |  |  |
Atlantic City Electric Company [Member] | Bloom Energy |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Atlantic City Electric Company [Member] | NET Power |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Atlantic City Electric Company [Member] | Other Equity Method Investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Equity Method Investments |  | 0 | 0 |  |  |  |
Atlantic City Electric Company [Member] | Employee benefit trusts and investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments | [6] | 0 | 0 |  |  |  |
Atlantic City Electric Company [Member] | Other available for sale investments |  |  |  |  |  |  |
Investments [Abstract] |  |  |  |  |  |  |
Available for sale investments |  | $ 0 | $ 0 |  |  |  |
[1] | Represents unbilled portion of receivables estimated under Exelon’s unbilled critical accounting policy.
[2] | Includes the estimated allowance for uncollectible accounts on billed customer and other accounts receivable.
[3] | For ComEd, BGE, Pepco and DPL, reflects the incremental allowance for uncollectible accounts recorded, which is in addition to the purchase discount. For ComEd, the incremental uncollectible accounts expense is recovered through a rate rider. BGE, Pepco and DPL recover actual write-offs which are reflected in the POR discount rate.
[4] | Primarily includes accrued payroll, bonuses and other incentives, vacation and benefits.
[5] | Includes investments in affiliated financing trusts, which were not consolidated within the financial statements of Exelon and are shown as investments in the Consolidated Balance Sheets. See Note 1 — Significant Accounting Policies for additional information.
[6] | The Registrants’ debt and equity security investments are recorded at fair market value.

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