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v3.24.3

Supplemental Financial Information - Cash Flow (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | $ 2,168 | $ 2,073
Amortization of regulatory assets |  |  | 507 | 537
Amortization of intangible assets, net |  |  | 6 | 6
Accretion expense |  |  | 2 | 0
Depreciation and amortization |  |  | 2,683 | 2,616
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | 181 | 152
Allowance for credit losses |  |  | 170 | 86
True-up adjustments to decoupling mechanisms and formula rates | $ (54) | $ 108 | (29) | 513
Amortization of operating ROU asset |  |  | 28 | 29
Change in environmental liabilities |  |  |  | 37
AFUDC - Equity | (38) | (40) | (116) | (113)
Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | 49 | (522)
Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | (116) | (113)
Commonwealth Edison Co |  |  |  |
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | 869 | 815
Amortization of regulatory assets |  |  | 255 | 230
Amortization of intangible assets, net |  |  | 0 | 0
Accretion expense |  |  | 0 | 0
Depreciation and amortization |  |  | 1,124 | 1,045
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | 53 | 19
Allowance for credit losses |  |  | 17 | 4
True-up adjustments to decoupling mechanisms and formula rates | (76) | 135 | (100) | 405
Amortization of operating ROU asset |  |  | 0 | 2
Change in environmental liabilities |  |  |  | 0
AFUDC - Equity | (13) | (7) | (32) | (25)
Commonwealth Edison Co | Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | 100 | (405)
Commonwealth Edison Co | Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | (32) | (25)
PECO Energy Co |  |  |  |
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | 308 | 287
Amortization of regulatory assets |  |  | 10 | 10
Amortization of intangible assets, net |  |  | 0 | 0
Accretion expense |  |  | 0 | 0
Depreciation and amortization |  |  | 318 | 297
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | (1) | (10)
Allowance for credit losses |  |  | 79 | 31
True-up adjustments to decoupling mechanisms and formula rates | 5 | 11 | 3 | 1
Amortization of operating ROU asset |  |  | 0 | 0
Change in environmental liabilities |  |  |  | 0
AFUDC - Equity | (7) | (10) | (24) | (22)
PECO Energy Co | Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | (3) | (1)
PECO Energy Co | Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | (24) | (22)
Baltimore Gas and Electric Company |  |  |  |
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | 369 | 381
Amortization of regulatory assets |  |  | 105 | 106
Amortization of intangible assets, net |  |  | 0 | 0
Accretion expense |  |  | 0 | 0
Depreciation and amortization |  |  | 474 | 487
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | 45 | 41
Allowance for credit losses |  |  | 23 | 4
True-up adjustments to decoupling mechanisms and formula rates | 9 | (22) | 28 | 47
Amortization of operating ROU asset |  |  | 5 | 4
Change in environmental liabilities |  |  |  | 0
AFUDC - Equity | (5) | (4) | (18) | (11)
Baltimore Gas and Electric Company | Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | (28) | (47)
Baltimore Gas and Electric Company | Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | (18) | (11)
Pepco Holdings LLC |  |  |  |
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | 581 | 550
Amortization of regulatory assets |  |  | 135 | 191
Amortization of intangible assets, net |  |  | 0 | 0
Accretion expense |  |  | 0 | 0
Depreciation and amortization |  |  | 716 | 741
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | 71 | 74
Allowance for credit losses |  |  | 51 | 47
True-up adjustments to decoupling mechanisms and formula rates | 8 | (15) | 40 | 59
Amortization of operating ROU asset |  |  | 19 | 21
Change in environmental liabilities |  |  |  | 37
AFUDC - Equity | (12) | (19) | (42) | (55)
Pepco Holdings LLC | Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | (20) | (69)
Pepco Holdings LLC | Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | (42) | (55)
Potomac Electric Power Company |  |  |  |
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | 249 | 232
Amortization of regulatory assets |  |  | 58 | 97
Amortization of intangible assets, net |  |  | 0 | 0
Accretion expense |  |  | 0 | 0
Depreciation and amortization |  |  | 307 | 329
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | 24 | 26
Allowance for credit losses |  |  | 25 | 27
True-up adjustments to decoupling mechanisms and formula rates | 5 | (18) | 42 | 28
Amortization of operating ROU asset |  |  | 4 | 5
Change in environmental liabilities |  |  |  | 37
AFUDC - Equity | (8) | (15) | (32) | (42)
Potomac Electric Power Company | Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | (42) | (28)
Potomac Electric Power Company | Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | (32) | (42)
Delmarva Power and Light Company |  |  |  |
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | 162 | 155
Amortization of regulatory assets |  |  | 21 | 27
Amortization of intangible assets, net |  |  | 0 | 0
Accretion expense |  |  | 0 | 0
Depreciation and amortization |  |  | 183 | 182
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | 11 | 13
Allowance for credit losses |  |  | 7 | 9
True-up adjustments to decoupling mechanisms and formula rates | (3) | (2) | 1 | 10
Amortization of operating ROU asset |  |  | 6 | 6
Change in environmental liabilities |  |  |  | 0
AFUDC - Equity | (3) | (3) | (9) | (7)
Delmarva Power and Light Company | Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | 7 | (15)
Delmarva Power and Light Company | Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | (9) | (7)
Atlantic City Electric Company |  |  |  |
Depreciation, Amortization and Accretion [Abstract] |  |  |  |
Property, plant and equipment |  |  | 158 | 145
Amortization of regulatory assets |  |  | 56 | 67
Amortization of intangible assets, net |  |  | 0 | 0
Accretion expense |  |  | 0 | 0
Depreciation and amortization |  |  | 214 | 212
Other Non-Cash Operating Activities [Abstract] |  |  |  |
Pension and non-pension postretirement benefit costs |  |  | 10 | 10
Allowance for credit losses |  |  | 19 | 11
True-up adjustments to decoupling mechanisms and formula rates | 6 | 5 | (3) | 21
Amortization of operating ROU asset |  |  | 2 | 2
Change in environmental liabilities |  |  |  | 0
AFUDC - Equity | $ (1) | $ (1) | (1) | (6)
Atlantic City Electric Company | Other Non-Cash Activity |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
True-up adjustments to decoupling mechanisms and formula rates |  |  | 15 | (26)
Atlantic City Electric Company | Return on borrowed funds |  |  |  |
Other Non-Cash Operating Activities [Abstract] |  |  |  |
AFUDC - Equity |  |  | $ (1) | $ (6)

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