Early Plant Retirements Early Plant Retirements (Details) - USD ($)
$ in Millions |
3 Months Ended |
|
Mar. 31, 2018 |
Mar. 31, 2017 |
Dec. 31, 2017 |
| Early Plant Retirements [Line Items] |
|
|
|
|
| Total Assets |
|
$ 42,790
|
|
$ 42,716
|
| Asset Retirement Obligations |
|
1,037
|
|
1,024
|
| Power [Member] |
|
|
|
|
| Early Plant Retirements [Line Items] |
|
|
|
|
| Total Assets |
|
12,263
|
|
12,418
|
| Asset Retirement Obligations |
|
821
|
|
$ 810
|
| Power [Member] | Energy Costs [Member] |
|
|
|
|
| Early Plant Retirements [Line Items] |
|
|
|
|
| Coal Inventory Lower of Cost or Market Adjustments |
|
4
|
$ 7
|
|
| Power [Member] | Depreciation And Amortization [Domain] |
|
|
|
|
| Early Plant Retirements [Line Items] |
|
|
|
|
| Accelerated Depreciation including Asset Retirement Costs |
|
|
$ 574
|
|
| Hope Creek [Member] |
|
|
|
|
| Early Plant Retirements [Line Items] |
|
|
|
|
| Materials and Supplies Inventory |
|
84
|
|
|
| Nuclear Production, net of Accumulated Depreciation |
|
602
|
|
|
| Nuclear Fuel In-Service, net of Accumulated Depreciation |
|
88
|
|
|
| Construction Work in Progress (including nuclear fuel) |
|
296
|
|
|
| Total Assets |
|
1,070
|
|
|
| Asset Retirement Obligations |
|
305
|
|
|
| Total Liabilities |
|
305
|
|
|
| Net Assets |
|
$ 765
|
|
|
| % Owned |
|
100.00%
|
|
|
| Nuclear Support Facilities [Member] |
|
|
|
|
| Early Plant Retirements [Line Items] |
|
|
|
|
| Materials and Supplies Inventory |
[1] |
$ 0
|
|
|
| Nuclear Production, net of Accumulated Depreciation |
[1] |
207
|
|
|
| Nuclear Fuel In-Service, net of Accumulated Depreciation |
[1] |
0
|
|
|
| Construction Work in Progress (including nuclear fuel) |
[1] |
1
|
|
|
| Total Assets |
[1] |
208
|
|
|
| Asset Retirement Obligations |
[1] |
0
|
|
|
| Total Liabilities |
[1] |
0
|
|
|
| Net Assets |
[1] |
208
|
|
|
| Salem [Member] |
|
|
|
|
| Early Plant Retirements [Line Items] |
|
|
|
|
| Materials and Supplies Inventory |
|
83
|
|
|
| Nuclear Production, net of Accumulated Depreciation |
|
653
|
|
|
| Nuclear Fuel In-Service, net of Accumulated Depreciation |
|
107
|
|
|
| Construction Work in Progress (including nuclear fuel) |
|
97
|
|
|
| Total Assets |
|
940
|
|
|
| Asset Retirement Obligations |
|
252
|
|
|
| Total Liabilities |
|
252
|
|
|
| Net Assets |
|
$ 688
|
|
|
| % Owned |
|
57.00%
|
|
|
| Peach Bottom [Member] |
|
|
|
|
| Early Plant Retirements [Line Items] |
|
|
|
|
| Materials and Supplies Inventory |
|
$ 41
|
|
|
| Nuclear Production, net of Accumulated Depreciation |
|
797
|
|
|
| Nuclear Fuel In-Service, net of Accumulated Depreciation |
|
136
|
|
|
| Construction Work in Progress (including nuclear fuel) |
|
20
|
|
|
| Total Assets |
|
994
|
|
|
| Asset Retirement Obligations |
|
207
|
|
|
| Total Liabilities |
|
207
|
|
|
| Net Assets |
|
$ 787
|
|
|
| % Owned |
|
50.00%
|
|
|
|
|