Represents the anticipated additional cost per month.

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Represents the estimated aggregate costs to suspend or cancel the project site.

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No definition available.

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Represents the amount paid per week, for certain engineering, procurement and management services.

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Represents information pertaining to the period of written notice to be sent in the event of non-renewal of letter of credit.

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The percentage of contract price provided as liquidated damages under the agreement.

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Represents the total nominally rated generating capacity per nuclear unit.

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Represents the additional number of units constructed in connection with the generation of nuclear energy.

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Represents the number of units constructed in connection with the generation of nuclear energy.

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Represents information pertaining to the project budget.

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No definition available.

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Information pertaining to the recovery of the the Guarantee Obligations assumed, represented as a percentage.

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No definition available.

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Represents information pertaining to the period of written notice to be sent to terminate the agreement.

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Represents the total investment made in additional vogtle units.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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The proportionate share of interest (percent) in a jointly owned utility plant.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of loss contingency liability.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Vogtle Units No. 3 and No. 4 Construction Project (Details) $ in Millions				1 Months Ended	6 Months Ended	12 Months Ended
	Jul. 31, 2017 USD ($)	Jun. 09, 2017 USD ($)	Mar. 29, 2017 USD ($)	Jan. 31, 2016 USD ($)	Jun. 30, 2017 USD ($) item	Dec. 31, 2008 USD ($) item MW	Mar. 28, 2017 USD ($)
Vogtle Units Number 3 And Number 4
Vogtle Units No. 3 and No. 4 Construction Project
Current investment					$ 3,700.0
Anticipated additional cost per month					70.0
Vogtle Units Number 3 And Number 4 \| Removal of Subcontractor liens
Vogtle Units No. 3 and No. 4 Construction Project
Aggregate liability paid or accrued					$ 354.0
Vogtle Units Number 3 And Number 4 \| Removal of Subcontractor liens \| Forecast
Vogtle Units No. 3 and No. 4 Construction Project
Liquidated damages	$ 120.0
Vogtle Units Number 3 And Number 4 \| Removal of Subcontractor liens \| The Contractor and WECTEC Staffing Services LLC \| Forecast
Vogtle Units No. 3 and No. 4 Construction Project
Liquidated damages	$ 400.0
Vogtle Units Number 3 And Number 4 \| Ownership participation agreement
Vogtle Units No. 3 and No. 4 Construction Project
Number of additional nuclear units \| item					2
Ownership interest (as a percent)					30.00%
Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Minimum
Vogtle Units No. 3 and No. 4 Construction Project
Estimated aggregate cancellation costs of site					$ 210.0
Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Maximum
Vogtle Units No. 3 and No. 4 Construction Project
Estimated aggregate cancellation costs of site					240.0
Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Westinghouse Electric Company LLC and Stone & Webster, Inc. (collectively, the Contractor)
Vogtle Units No. 3 and No. 4 Construction Project
Number of nuclear units \| item						2
Generating capacity of each nuclear unit \| MW						1,100
Project budget							$ 5,000.0
Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Westinghouse Electric Company LLC and Stone & Webster, Inc. (collectively, the Contractor) \| In the event of abandonment of work
Vogtle Units No. 3 and No. 4 Construction Project
Liquidated damages, as a percent of contract price						40.00%
Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Westinghouse Electric Company LLC and Stone & Webster, Inc. (collectively, the Contractor) \| Minimum
Vogtle Units No. 3 and No. 4 Construction Project
Project budget					6,500.0
Estimated aggregate cancellation costs of site					700.0
Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Westinghouse Electric Company LLC and Stone & Webster, Inc. (collectively, the Contractor) \| Maximum
Vogtle Units No. 3 and No. 4 Construction Project
Liquidated damages, as a percent of contract price						10.00%
Liquidated damages						$ 920.0
Project budget					7,300.0
Estimated aggregate cancellation costs of site					800.0
Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Westinghouse Electric Company LLC
Vogtle Units No. 3 and No. 4 Construction Project
Written notice period for non-renewal of letter of credit				60 days
Vogtle Units Number 3 And Number 4 \| Interim Assessment Agreement
Vogtle Units No. 3 and No. 4 Construction Project
Liquidated damages					195.0
Vogtle Units Number 3 And Number 4 \| Interim Assessment Agreement \| The Contractor and WECTEC Staffing Services LLC
Vogtle Units No. 3 and No. 4 Construction Project
Liquidated damages					650.0
Amount paid for services, per week			$ 5.4
Aggregate liability paid or accrued					$ 552.0
Vogtle Units Number 3 And Number 4 \| Guarantee Settlement Agreement
Vogtle Units No. 3 and No. 4 Construction Project
Guarantee obligations, maximum exposure		$ 1,100.0
Vogtle Units Number 3 And Number 4 \| Guarantee Settlement Agreement \| The Co-owners and Toshiba
Vogtle Units No. 3 and No. 4 Construction Project
Guarantee obligations, maximum exposure		$ 3,680.0
Recovery of guarantee obligations assumed (as a percent)					100.00%
Vogtle Units Number 3 And Number 4 \| Amended and Restated Services Agreement \| Westinghouse Electric Company LLC and Stone & Webster, Inc. (collectively, the Contractor)
Vogtle Units No. 3 and No. 4 Construction Project
Written notice period for termination of agreement		30 days
Toshiba Corporation
Vogtle Units No. 3 and No. 4 Construction Project
Shareholder's equity negative balance					$ 4,500.0
Toshiba Corporation \| Vogtle Units Number 3 And Number 4 \| Engineering, Procurement and Construction Agreement (the EPC Agreement) \| Westinghouse Electric Company LLC
Vogtle Units No. 3 and No. 4 Construction Project
Letters of credit				$ 920.0