Summary of Operations and Significant Accounting Policies - Cash and cash Equivalents - Additional Information (Details)	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Concentration Risk [Line Items]
Percentage of cash balances	56.00%	84.00%
Investment, Type [Extensible Enumeration]	U S Treasuries And F D I C Insured [Member]	U S Treasuries And F D I C Insured [Member]

Indicates type of investment. Includes, but is not limited to, common stock, preferred stock, convertible security, fixed income security, government security, option purchased, warrant, loan participation and assignment, commercial paper, bankers' acceptance, certificates of deposit, short-term security, repurchase agreement, and other investment company.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
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-URI https://asc.fasb.org//1943274/2147480524/946-210-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 320
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-Section S99
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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+ Details