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Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Sep. 30, 2024 | Sep. 30, 2023
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items] |  |
Net unrealized gains (losses) | $ 2,412,000 | $ 4,316,000
Transfers of investments between Level 1 and Level 2 | 0 | 0
Impairment loss recognized on an asset group | 0 | 0
Valuation allowance | 0 | 0
Contract assets | 9,339,000 | 1,508,000
Net revenue | 113,166,000 | 105,075,000
Accounts receivable related to contracts with customers | 163,000 | 114,000
Total long-term assets | $ 15,279,000 | 16,970,000
Fair Value Measurement Asset Transfers Net |  | 10,000,000
Maximum [Member] |  |
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items] |  |
Contract assets collection period | 1 year |
Current Liabilities [Member] |  |
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items] |  |
Customer deposits related to contracts with customers | $ 5,018,000 | $ 6,815,000
Entities Owned by One Global Company [Member] | Revenue [Member] | Customer One [Member] |  |
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items] |  |
Percentage of Concentration Risk | 11.30% | 14.80%
Three to Four Years Old Inventory [Member] |  |
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items] |  |
Inventory, maximum time period on the shelf, years | 4 years |
Cost basis reduction in inventory, percentage | 50.00% |
Four to Five Years Old Inventory [Member] |  |
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items] |  |
Inventory, maximum time period on the shelf, years | 5 years |
Cost basis reduction in inventory, percentage | 75.00% |
Greater Than Five Years Old Inventory [Member] |  |
Nature Of Operations And Summary Of Significant Accounting Policies [Line Items] |  |
Inventory, minimum time period on the shelf, years | 5 years |
Inventory valuation estimate | $ 0 |

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