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Financial Instruments - Summary of Interest Rate Swaps Held (Details)	Jun. 30, 2021 USD ($) interest_rate_swap	Jan. 31, 2021 USD ($) interest_rate_swap	Dec. 31, 2020 USD ($)
Derivative [Line Items]
Total swap notional amount	$ 29,426,000,000		$ 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 (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

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