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- Definition

Development regulatory and sales milestones payments.

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- Definition

Increase decrease in cash and investments.

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- Definition

Number Of Subsidiaries With Foreign Currency As Functional Currency

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- Definition

Organization and significant accounting policies.

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- Definition

Proceeds From Collaboration Arrangements

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No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount of cash and cash equivalent, and cash and cash equivalent restricted to withdrawal or usage; attributable to continuing operation. 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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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Amount of cash and cash equivalent restricted as to withdrawal or usage, classified as current. 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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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Organization and Significant Accounting Policies - Narrative (Details)						1 Months Ended	12 Months Ended
	Aug. 13, 2025 USD ($)	Feb. 24, 2025 USD ($)	Feb. 14, 2025 USD ($)	Feb. 07, 2025 USD ($)	Nov. 25, 2024 USD ($)	Aug. 31, 2025 USD ($)	Sep. 30, 2025 USD ($) segment subsidiary	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Organization And Significant Accounting Policies [Line Items]
Cash, cash equivalents and restricted cash							$ 226,548,000	$ 102,685,000	$ 110,891,000	$ 108,005,000
Restricted cash							1,900,000	3,500,000
Available-for-sale securities, at fair value							692,818,000	578,276,000
Net increase (decrease) in cash and investments							238,400,000
Value of stock repurchased							53,193,000
Interest income							37,289,000	22,720,000	15,299,000
Proceeds from the issuance of warrants					$ 25,000,000.0		25,000,000	0	0
Repayments of credit facility							201,625,000	0	0
Capital expenditure							22,666,000	141,469,000	176,737,000
Development regulatory and sales milestones payments							13,400,000,000
Intangible assets subject to amortization, impairment							$ 0	$ 0	$ 0
Number of subsidiaries with foreign currency as functional currency \| subsidiary							3
Number of operating segments \| segment							1
Sarepta \| Sarepta Collaboration Agreement
Organization And Significant Accounting Policies [Line Items]
Proceeds from collaboration arrangements	$ 50,000,000	$ 500,000,000	$ 500,000,000			$ 50,000,000.0
Proceeds from issuance of equity				$ 325,000,000.0
Development milestone payments						100,000,000.0
Value of stock repurchased	$ 50,000,000					$ 50,000,000