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v3.21.1

Long-Term Debt - Long-Term Debt (Parenthetical) (Detail) | 3 Months Ended
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Mar. 31, 2021
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%
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%

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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