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 ($)							1 Months Ended	12 Months Ended
	Dec. 20, 2023	Nov. 24, 2023	Apr. 03, 2023	Mar. 01, 2023	Dec. 13, 2022	Dec. 17, 2021	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Jan. 01, 2023	Dec. 14, 2022	May 25, 2021
Line Of Credit Facility [Line Items]
Commitment fees, percentage								0.125%
Weighted-average interest rate							5.68%	5.68%	5.00%
Repayment of short term debt							$ 400,000,000
Line of credit facility maximum borrowing capacity							1,200,000,000	$ 1,200,000,000	$ 1,200,000,000
Increase of credit facility						$ 100,000,000
Affiliate [Member]
Line Of Credit Facility [Line Items]
Repayment of note payable							$ 195,000,000
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.
Debt instrument term							5 years
Repayment of note payable							$ 149,000,000
364-day Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity			$ 200,000,000	$ 200,000,000
Credit facility maturity date			Apr. 01, 2024	Feb. 28, 2024
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. 13, 2023			Dec. 16, 2022			Dec. 13, 2023
Term Loan [Member]
Line Of Credit Facility [Line Items]
Principal amount										$ 670,000,000
Repayment of short term debt	$ 670,000,000
Proceeds from short term debt	670,000,000
Revolving Loan [Member]
Line Of Credit Facility [Line Items]
Principal amount										$ 66,000,000
Repayment of short term debt	286,000,000
Proceeds from short term debt	$ 286,000,000
1-year Term Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility maturity date			Apr. 01, 2024	Feb. 28, 2024				Dec. 13, 2022	Dec. 13, 2022
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				$ 800,000,000