v3.26.1
Fair Value Measurements and Investments (Tables)
 6 Months Ended
Mar. 31, 2026
Fair Value Disclosures [Abstract]  
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis
Assets and Liabilities Measured at Fair Value on a Recurring Basis
 Fair Value Measurements
Using Inputs Considered as
 Level 1Level 2
 March 31,
2026		September 30,
2025		March 31,
2026		September 30,
2025
 (in millions)
Assets
Cash equivalents and restricted cash equivalents:
Money market funds
$8,154 $13,760 $— $— 
Investment securities:
Marketable equity securities
424 411 — — 
U.S. government-sponsored debt securities
— — 129 305 
U.S. Treasury securities
1,264 2,116 — — 
Other current and non-current assets:
Money market funds
33 28 — — 
Derivative instruments
— — 159 62 
Total $9,875 $16,315 $288 $367 
Liabilities
Accrued compensation and benefits:
Deferred compensation liability
$266 $268 $— $— 
Accrued and other liabilities:
Derivative instruments
— — 234 319 
Total $266 $268 $234 $319 
Schedule of Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value of Debt Securities
The amortized cost, gross unrealized gains and losses and fair value of debt securities were as follows:
March 31, 2026
Amortized
Cost		Gross UnrealizedFair
Value
GainsLosses
(in millions)
U.S. government-sponsored debt securities$129 $— $— $129 
U.S. Treasury securities1,257 7 — 1,264 
Total$1,386 $7 $— $1,393 
September 30, 2025
Amortized
Cost		Gross UnrealizedFair
Value
GainsLosses
(in millions)
U.S. government-sponsored debt securities$304 $1 $— $305 
U.S. Treasury securities2,101 15 — 2,116 
Total$2,405 $16 $— $2,421 
Schedule of Debt Securities Classified by Contractual Maturity Date
The stated maturities of debt securities were as follows:
March 31,
2026
 (in millions)
Due within one year$1,243 
Due after one year through five years
150 
Total$1,393 
Schedule of Non-Marketable Equity Securities
The following table summarizes the Company’s non-marketable equity securities held as of period end that were accounted for using the fair value measurement alternative:
March 31,
2026		September 30,
2025
(in millions)
Initial cost basis
$712 $711 
Adjustments:
Upward adjustments
574 564 
Downward adjustments, including impairment
(219)(219)
Carrying amount
$1,067 $1,056 
Unrealized gains and losses of the Company’s non-marketable equity securities held as of period end that were accounted for using the fair value measurement alternative were as follows:
Three Months Ended
March 31,		Six Months Ended
March 31,
2026202520262025
(in millions)
Upward adjustments$7 $7 $10 $7 
Downward adjustments, including impairment
$— $(31)$— $(49)