CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2025	Sep. 30, 2024
Reconciliation of cash, cash equivalents and restricted cash and cash equivalents at end of period:
Cash and cash equivalents	$ 175	$ 614
Restricted cash and cash equivalents included in other current assets	$ 60	$ 4
Restricted Cash and Cash Equivalents, Current, Statement of Financial Position [Extensible Enumeration]	Other Assets, Current	Other Assets, Current
Restricted cash and cash equivalents included in restricted funds	$ 73	$ 69
Restricted Cash and Cash Equivalents, Noncurrent, Statement of Financial Position [Extensible Enumeration]	Restricted Cash and Investments, Noncurrent	Restricted Cash and Investments, Noncurrent
Cash, cash equivalents and restricted cash and cash equivalents at end of period	$ 308	$ 687

Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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