v3.20.2

Debt (Consolidated Debt) (Details) - USD ($) | Sep. 30, 2020 | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | $ 4,948,000,000 |  | $ 4,750,000,000
Unamortized debt issuance costs | (37,407,000) |  | (35,263,000)
Net unamortized premium (discount) | (10,282,000) |  | (8,662,000)
Long-term debt, net | $ 4,900,311,000 |  | 4,706,075,000
4.25% Notes Due 2021 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.25% |  |
Debt Instrument, Face Amount | $ 0 |  | 550,000,000
3.20% Notes Due 2025 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.20% |  |
Debt Instrument, Face Amount | $ 250,000,000 |  | 250,000,000
5.00% Notes Due 2026 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.00% |  |
Debt Instrument, Face Amount | $ 650,000,000 |  | 650,000,000
3.25% Notes Due 2030 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.25% | 3.25% |
Debt Instrument, Face Amount | $ 500,000,000 | $ 500,000,000.0 | 0
6.40% Notes Due 2037 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 6.40% |  |
Debt Instrument, Face Amount | $ 250,000,000 |  | 250,000,000
4.20% Notes Due 2042 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.20% |  |
Debt Instrument, Face Amount | $ 250,000,000 |  | 250,000,000
5.15% Notes Due 2043 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.15% |  |
Debt Instrument, Face Amount | $ 550,000,000 |  | 550,000,000
4.20% Notes Due 2045 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.20% |  |
Debt Instrument, Face Amount | $ 250,000,000 |  | 250,000,000
4.25% Notes Due 2046 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.25% |  |
Debt Instrument, Face Amount | $ 500,000,000 |  | 500,000,000
4.20% Notes Due 2047 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.20% |  |
Debt Instrument, Face Amount | $ 500,000,000 |  | 500,000,000
4.85% Notes Due 2049 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 4.85% |  |
Debt Instrument, Face Amount | $ 500,000,000 |  | 500,000,000
3.95% Notes Due 2050 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.95% |  |
Debt Instrument, Face Amount | $ 500,000,000 |  | 500,000,000
Commercial Paper [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Debt Instrument, Face Amount | $ 248,000,000 |  | $ 0

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