Shareholders' Equity and Stock-Based Compensation - Additional Information (Detail)	12 Months Ended
Sep. 30, 2025
Common Stock [Member]
Class of Stock [Line Items]
Right of holders to elect company's board of directors	25.00%
Class B common stock [Member]
Class of Stock [Line Items]
Right of holders to elect company's board of directors	75.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details