Date hedged through in cash flow hedge.

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Franchise fees and gross receipts taxes.

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Gain (loss) on issuance of shares on transfer of assets.

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Summary of significant accounting policies.

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- Definition

The average discount rate applied to insurance contracts to determine future policy benefits to be paid to or on behalf of policyholders.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Indicates line item in statement of financial position that includes derivative asset.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Indicates line item in statement of financial position that includes derivative liability.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets.

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Effective rate, including composite rate, of cost of financing additions to qualifying regulated assets, commonly called allowance for funds used during construction.

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Composite depreciation rate for public utility plants in service.

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No definition available.

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- Definition

Amount due from customers for fees and charges arising from transactions related to the entity's brokerage activities and operations.

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Number of shares of stock issued during the period as part of a transaction to acquire assets that do not qualify as a business combination.

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Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

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Significant Accounting Policies - Additional Information (Detail)		12 Months Ended
	Jan. 01, 2023 USD ($) shares	Dec. 31, 2022 USD ($) Segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| Segment		2
Percentage of original cost of depreciable property		3.20%	3.50%	3.20%
Depreciation expense		$ 402,000,000	$ 408,000,000	$ 381,000,000
Allowance for funds used during construction rate		6.00%	6.46%	6.46%
Allowance for funds used during construction		$ 6,000,000	$ 66,000,000	$ 44,000,000
Receivables from contracts with customers		295,000,000	252,000,000
Unbilled revenues		82,000,000	74,000,000
Franchise fees and gross receipts taxes		145,000,000	129,000,000	$ 109,000,000
Derivative Liabilities		$ 1,000,000	$ 0
Derivative Liability, Statement of Financial Position [Extensible Enumeration]		Other Liabilities, Current	Other Liabilities, Current
Derivative Assets		$ 5,000,000	$ 0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Prepaid Expense and Other Assets, Current	Prepaid Expense and Other Assets, Current
Subsequent Event [Member]
Summary Of Significant Accounting Policies [Line Items]
Issuance of common stock on transfer of assets \| shares	100
Gain (loss) from transaction	$ 0
Subsequent Event [Member] \| Term Loan [Member]
Summary Of Significant Accounting Policies [Line Items]
Principal amount	670,000,000
Subsequent Event [Member] \| Revolving Loan [Member]
Summary Of Significant Accounting Policies [Line Items]
Principal amount	$ 66,000,000
Natural Gas Contracts [Member]
Summary Of Significant Accounting Policies [Line Items]
Maximum length of time hedging in future cash flow		Nov. 30, 2018
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Discount rates used in estimating other self-insurance liabilities		4.00%	1.63%
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Discount rates used in estimating other self-insurance liabilities		0.78%	4.00%
PGS [Member]
Summary Of Significant Accounting Policies [Line Items]
Allowance for funds used during construction rate		6.00%	6.00%	5.97%
Tampa Electric [Member]
Summary Of Significant Accounting Policies [Line Items]
Depreciation expense		$ 359,000,000	$ 357,000,000	$ 339,000,000