Fair Value of Financial Instruments (Details) - Senior Notes - USD ($)	Jun. 30, 2020	Jun. 22, 2020
$600 2.000% senior notes due 2030
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt		$ 600,000,000.0
Fixed interest rate		2.00%
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed rate senior notes carrying amount	$ 5,900,000,000
Fair Value, Inputs, Level 2 \| $600 3.000% senior notes due 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 600,000,000
Fixed interest rate	3.00%
Long-term debt, fair value	$ 606,000,000
Fair Value, Inputs, Level 2 \| $500 2.800% senior notes due 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 500,000,000
Fixed interest rate	2.80%
Long-term debt, fair value	$ 515,000,000
Fair Value, Inputs, Level 2 \| $500 3.125% senior notes due 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 500,000,000
Fixed interest rate	3.125%
Long-term debt, fair value	$ 524,000,000
Fair Value, Inputs, Level 2 \| $700 3.650% senior notes due 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 700,000,000
Fixed interest rate	3.65%
Long-term debt, fair value	$ 761,000,000
Fair Value, Inputs, Level 2 \| $500 2.350% senior notes due 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 500,000,000
Fixed interest rate	2.35%
Long-term debt, fair value	$ 532,000,000
Fair Value, Inputs, Level 2 \| $300 3.850% senior notes due 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 300,000,000
Fixed interest rate	3.85%
Long-term debt, fair value	$ 341,000,000
Fair Value, Inputs, Level 2 \| $700 3.800% senior notes due 2026
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 700,000,000
Fixed interest rate	3.80%
Long-term debt, fair value	$ 801,000,000
Fair Value, Inputs, Level 2 \| $800 4.200% senior notes due 2028
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 800,000,000
Fixed interest rate	4.20%
Long-term debt, fair value	$ 938,000,000
Fair Value, Inputs, Level 2 \| $700 2.950% senior notes due 2029
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 700,000,000
Fixed interest rate	2.95%
Long-term debt, fair value	$ 764,000,000
Fair Value, Inputs, Level 2 \| $600 2.000% senior notes due 2030
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Face amount of debt	$ 600,000,000
Fixed interest rate	2.00%
Long-term debt, fair value	$ 601,000,000

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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