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Fair Value Measurements - Carrying and Estimated Fair Value of Debt (Details) - USD ($) $ in Millions	Jun. 30, 2023	May 01, 2020
Convertible Debt
Debt Instrument [Line Items]
Stated interest rate		1.25%
Convertible Debt \| 1.25% Convertible Notes due 2025
Debt Instrument [Line Items]
Stated interest rate	1.25%
Carrying value	$ 1,611
Unsecured Debt \| 5.25% Notes due 2025
Debt Instrument [Line Items]
Stated interest rate	5.25%
Carrying value	$ 1,302
Unsecured Debt \| 3.00% Notes due 2026
Debt Instrument [Line Items]
Stated interest rate	3.00%
Carrying value	$ 300
Unsecured Debt \| 3.45% Notes due 2027
Debt Instrument [Line Items]
Stated interest rate	3.45%
Carrying value	$ 300
Unsecured Debt \| 5.125% Notes due 2027
Debt Instrument [Line Items]
Stated interest rate	5.125%
Carrying value	$ 1,727
Unsecured Debt \| 7.375% Debentures due 2027
Debt Instrument [Line Items]
Stated interest rate	7.375%
Carrying value	$ 112
Unsecured Debt \| 2.625% Notes due 2030
Debt Instrument [Line Items]
Stated interest rate	2.625%
Carrying value	$ 500
Unsecured Debt \| 1.000% PSP1 Loan due 2030
Debt Instrument [Line Items]
Stated interest rate	1.00%
Carrying value	$ 976
Unsecured Debt \| 1.000% PSP2 Loan due 2031
Debt Instrument [Line Items]
Stated interest rate	1.00%
Carrying value	$ 566
Unsecured Debt \| 1.000% PSP3 Loan due 2031
Debt Instrument [Line Items]
Stated interest rate	1.00%
Carrying value	$ 526
Level 2 \| Convertible Debt \| 1.25% Convertible Notes due 2025
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	1,861
Level 2 \| Unsecured Debt \| 5.25% Notes due 2025
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	1,291
Level 2 \| Unsecured Debt \| 3.00% Notes due 2026
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	276
Level 2 \| Unsecured Debt \| 3.45% Notes due 2027
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	276
Level 2 \| Unsecured Debt \| 5.125% Notes due 2027
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	1,715
Level 2 \| Unsecured Debt \| 7.375% Debentures due 2027
Debt Instrument [Line Items]
Loans payable, Estimated Fair Value	118
Level 2 \| Unsecured Debt \| 2.625% Notes due 2030
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	426
Level 3 \| Unsecured Debt \| 1.000% PSP1 Loan due 2030
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	866
Level 3 \| Unsecured Debt \| 1.000% PSP2 Loan due 2031
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	496
Level 3 \| Unsecured Debt \| 1.000% PSP3 Loan due 2031
Debt Instrument [Line Items]
Notes payable, Estimated Fair Value	$ 456