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Financial Instruments - Summary of Interest Rate Swaps Held (Details)	Sep. 30, 2020 USD ($) interest_rate_swap	Jun. 30, 2020 USD ($)	Feb. 29, 2020 USD ($) interest_rate_swap	Dec. 31, 2019 USD ($)
Derivative [Line Items]
Par Value of Debt		$ 4,500,000,000
Total swap notional amount	$ 27,151,000,000			$ 30,666,000,000
Interest rate swap contracts
Derivative [Line Items]
Number of Interest Rate Swaps Held (in interest rate swaps) | interest_rate_swap	14		5
Total swap notional amount			$ 250,000,000
3.875% notes due 2021 | Interest rate swap contracts
Derivative [Line Items]
Stated interest rate (as percent)	3.875%
Par Value of Debt	$ 1,150,000,000
Number of Interest Rate Swaps Held (in interest rate swaps) | interest_rate_swap	5
Total swap notional amount	$ 1,150,000,000
2.40% notes due 2022 | Interest rate swap contracts
Derivative [Line Items]
Stated interest rate (as percent)	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 (as percent)	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

X

- Definition

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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