XML 59 R44.htm IDEA: XBRL DOCUMENT v3.23.2
Fair Value Measurements and Investments - Continuous Unrealized Losses for Less than 12 Months and More than 12 Months (Details) - USD ($)
$ in Millions
Jun. 30, 2023
Sep. 30, 2022
Debt Securities, Available-for-Sale [Line Items]    
Less Than 12 Months, Fair Value $ 2,108 $ 3,915
Less Than 12 Months, Gross Unrealized Losses (19) (134)
12 Months or Greater, Fair Value 2,165  
12 Months or Greater, Gross Unrealized Losses (82)  
U.S. government-sponsored debt securities    
Debt Securities, Available-for-Sale [Line Items]    
Less Than 12 Months, Fair Value 584 408
Less Than 12 Months, Gross Unrealized Losses (2) (1)
12 Months or Greater, Fair Value 0  
12 Months or Greater, Gross Unrealized Losses 0  
U.S. Treasury securities    
Debt Securities, Available-for-Sale [Line Items]    
Less Than 12 Months, Fair Value 1,524 3,507
Less Than 12 Months, Gross Unrealized Losses (17) $ (133)
12 Months or Greater, Fair Value 2,165  
12 Months or Greater, Gross Unrealized Losses $ (82)