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Debt - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Mar. 31, 2026	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Mar. 31, 2022	Aug. 31, 2016
Debt Instrument [Line Items]
Long-term debt, current maturities			$ 0		$ 0
Net proceeds from debt issuances	$ 1,487,000,000	$ 1,487,000,000	0
Senior Notes 2.45% Due 2027
Debt Instrument [Line Items]
Long-term debt, current maturities	500,000,000	500,000,000
Debt, stated interest rate							2.45%
Debt, face amount							$ 500,000,000
Senior Notes 2.50% Due 2027
Debt Instrument [Line Items]
Long-term debt, current maturities	$ 500,000,000	$ 500,000,000
Debt, stated interest rate						2.50%
Debt, face amount						$ 500,000,000
Senior Notes 4.60% Due 2031
Debt Instrument [Line Items]
Debt, stated interest rate	4.60%	4.60%
Debt, face amount	$ 500,000,000	$ 500,000,000
Senior Notes 5.15% Due 2036
Debt Instrument [Line Items]
Debt, stated interest rate	5.15%	5.15%
Debt, face amount	$ 1,000,000,000	$ 1,000,000,000
Discretionary Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 300,000,000	300,000,000
Borrowings outstanding		$ 0	$ 0	$ 0