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Regulatory Matters - GPC Amendments to the Vogtle Joint Ownership Agreements (Details) - USD ($) |  | 1 Months Ended | 6 Months Ended | 12003 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 11, 2018 | Sep. 30, 2022 | Jun. 30, 2023 | Dec. 31, 2022 | Jul. 31, 2022 | Jun. 30, 2022 | Aug. 31, 2018
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Agreement with third party, amount of costs over projected forecast to be paid by company |  | 20.00% |  |  |  |  |
GEORGIA POWER CO |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Pre-tax charge to income |  |  |  | $ 407,000,000 |  |  |
After tax charge to income |  |  |  | 304,000,000 |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Production tax credits, aggregate purchase price, maximum |  |  | $ 300,000,000 |  |  |  |
Preliminary estimated cost to complete |  |  | $ 10,593,000,000 |  |  |  |
Additional construction capital costs | $ 3,300,000,000 |  |  | $ 345,000,000 |  |  |
Remaining share of construction costs, agreement to pay, percentage |  |  | 100.00% |  |  |  |
Percentage of ownership interest required for voting for continuing construction |  |  |  |  |  |  | 90.00%
Percentage of costs, disallowed for recovery |  |  | 6.00% |  |  |  |
Costs disallowed for recovery, period |  |  | 6 months |  |  |  |
Public utilities, extension project schedule, term |  |  | 1 year |  |  |  |
Estimated cost to complete, starting dollar amount |  |  |  |  | $ 18,380,000,000 |  |
Proportionate ownership share |  |  | 45.70% |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Vogtle Owners |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Additional construction capital costs |  |  | $ 100,000 |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Vogtle Owners | Tender Provision Dispute |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Estimated cost to complete, starting dollar amount |  |  |  |  |  | $ 17,100,000,000 |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | MEAG Power |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Payment of power costs |  | $ 92,000,000 |  |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category I |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Preliminary estimated cost to complete |  |  | 8,400,000,000 |  |  |  |
Additional construction capital costs, threshold |  |  | $ 800,000,000 |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category II |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Percentage of construction costs, responsibility to pay |  |  | 55.70% |  |  |  |
Additional construction capital costs |  |  | $ 80,000,000 |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category II | Vogtle Owners |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Percentage of construction costs, responsibility to pay |  |  | 44.30% |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category II | Minimum |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Additional construction capital costs, threshold |  |  | $ 800,000,000 |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category II | Maximum |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Additional construction capital costs, threshold |  |  | $ 1,600,000,000 |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category III |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Percentage of construction costs, responsibility to pay |  |  | 65.70% |  |  |  |
Additional construction capital costs |  |  | $ 100,000,000 |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category III | Vogtle Owners |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Percentage of construction costs, responsibility to pay |  |  | 34.30% |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category III | Minimum |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Additional construction capital costs, threshold |  |  | $ 1,600,000,000 |  |  |  |
Plant Vogtle Units 3 And 4 | GEORGIA POWER CO | Category III | Maximum |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |
Additional construction capital costs, threshold |  |  | $ 2,100,000,000 |  |  |  |

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