| Balance Sheet Information (Narrative) (Details) - USD ($) | 3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
| Mar. 31, 2023 | Mar. 31, 2022 | Mar. 31, 2023 | Mar. 31, 2022 | Sep. 30, 2022 | |
| Property, Plant and Equipment [Line Items] | |||||
| Depreciation expense | $ 48,000 | $ 30,000 | $ 93,000 | $ 55,000 | |
| Equipment, Furniture And Leasehold Improvements [Member] | |||||
| Property, Plant and Equipment [Line Items] | |||||
| Deposits | $ 525,000 | $ 525,000 | $ 276,000 | ||
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- Definition The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition 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. No definition available. 
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- Details 
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