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Financial Instruments - Summary of Interest Rate Swaps Held (Details) | Sep. 30, 2021 USD ($) interest_rate_swap | Jan. 31, 2021 USD ($) interest_rate_swap | Dec. 31, 2020 USD ($)
--- | --- | --- | ---
Derivative [Line Items] |  |  |
Total swap notional amount | $ 28,458,000,000 |  | $ 32,784,000,000
Interest rate swap contracts |  |  |
Derivative [Line Items] |  |  |
Number of Interest Rate Swaps Held (in interest rate swaps) | interest_rate_swap | 9 | 5 |
Total swap notional amount |  | $ 1,150,000,000 |
2.40% notes due 2022 | Interest rate swap contracts |  |  |
Derivative [Line Items] |  |  |
Stated interest rate | 2.40% |  |
Par Value of Debt | $ 1,000,000,000 |  |
Number of Interest Rate Swaps Held (in interest rate swaps) | interest_rate_swap | 4 |  |
Total swap notional amount | $ 1,000,000,000 |  |
2.35% notes due 2022 | Interest rate swap contracts |  |  |
Derivative [Line Items] |  |  |
Stated interest rate | 2.35% |  |
Par Value of Debt | $ 1,250,000,000 |  |
Number of Interest Rate Swaps Held (in interest rate swaps) | interest_rate_swap | 5 |  |
Total swap notional amount | $ 1,250,000,000 |  |

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