Significant Financing Transactions (Commercial Paper, Bank Loans and Letters of Credit Outstanding) (Detail) |
Jun. 30, 2026
USD ($)
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|---|---|---|---|---|---|---|---|---|
| Line of Credit Facility [Line Items] | ||||||||
| Facility Limit | $ 8,000,000,000 | |||||||
| Outstanding Commercial Paper | 2,087,000,000 | |||||||
| Outstanding Letters of Credit | 4,000,000 | |||||||
| Facility Capacity Available | 5,909,000,000 | |||||||
| Joint Revolving Credit Facility | ||||||||
| Line of Credit Facility [Line Items] | ||||||||
| Facility Limit | 7,000,000,000 | [1] | ||||||
| Outstanding Commercial Paper | 2,087,000,000 | [1] | ||||||
| Outstanding Letters of Credit | 4,000,000 | [1] | ||||||
| Facility Capacity Available | 4,909,000,000 | [1] | ||||||
| Supplemental Revolving Credit Facility | ||||||||
| Line of Credit Facility [Line Items] | ||||||||
| Facility Limit | 1,000,000,000 | [2] | ||||||
| Outstanding Commercial Paper | 0 | [2] | ||||||
| Facility Capacity Available | 1,000,000,000 | [2] | ||||||
| Virginia Electric and Power Company | ||||||||
| Line of Credit Facility [Line Items] | ||||||||
| Facility Limit | 7,000,000,000 | [3] | ||||||
| Outstanding Commercial Paper | 992,000,000 | [3] | ||||||
| Outstanding Letters of Credit | $ 1,000,000 | [3] | ||||||
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