Long-Term Debt - Long-Term Debt (Parenthetical) (Detail)	6 Months Ended
	Jun. 30, 2022
0.650% Senior Notes, Due 2023
Debt Instrument [Line Items]
Maturity year	2023
Interest rate on notes	0.65%
4.25% Senior Notes, Due 2024
Debt Instrument [Line Items]
Maturity year	2024
Interest rate on notes	4.25%
7% Debentures, Due 2025
Debt Instrument [Line Items]
Maturity year	2025
Interest rate on notes	7.00%
3.450% Senior Notes, Due 2027
Debt Instrument [Line Items]
Maturity year	2027
Interest rate on notes	3.45%
3.500% Senior Notes, Due 2027
Debt Instrument [Line Items]
Maturity year	2027
Interest rate on notes	3.50%
2.500% Senior Notes, Due 2030
Debt Instrument [Line Items]
Maturity year	2030
Interest rate on notes	2.50%
2.400% Senior Notes, Due 2031
Debt Instrument [Line Items]
Maturity year	2031
Interest rate on notes	2.40%
6.25% Senior Notes, Due 2037
Debt Instrument [Line Items]
Maturity year	2037
Interest rate on notes	6.25%
4.250% Senior Notes, Due 2047
Debt Instrument [Line Items]
Maturity year	2047
Interest rate on notes	4.25%
3.200% Senior Notes, Due 2051
Debt Instrument [Line Items]
Maturity year	2051
Interest rate on notes	3.20%