Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Short-Term Debt - Additional Information (Detail) - USD ($)			12 Months Ended
	Dec. 13, 2022	Dec. 17, 2021	Dec. 31, 2022	Dec. 14, 2022	Dec. 31, 2021	May 25, 2021
Line Of Credit Facility [Line Items]
Commitment fees, percentage			0.125%
Weighted-average interest rate			5.00%		0.58%
Line of credit facility maximum borrowing capacity			$ 1,200,000,000		$ 1,300,000,000
Increase of credit facility		$ 100,000,000
Commercial Paper Program [Member]
Line Of Credit Facility [Line Items]
Debt instrument, restrictive covenants			The maturities of the Notes will vary, but may not exceed 270 days from the date of issue.
TEC Term Loan [Member]
Line Of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity	$ 500,000,000			$ 400,000,000
Credit facility maturity date	Dec. 16, 2022		Dec. 13, 2023
Minimum [Member] \| Amended And Restated Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Debt instrument maturity date		Mar. 22, 2023
Maximum [Member] \| Amended And Restated Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Debt instrument maturity date		Dec. 17, 2026
Maximum [Member] \| Commercial Paper Program [Member]
Line Of Credit Facility [Line Items]
Commercial paper issued			$ 800,000,000			$ 800,000,000