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Nature of Business and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jul. 01, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Jun. 30, 2020
Significant Accounting Policies [Line Items] |  |  |  |
Carrying amount of long-term debt, including current portion |  | $ 3,470,000 |  | $ 2,110,000
Short-term time deposits |  | 460,000 |  | $ 460,000
Intangible assets amortization expense |  | 106,000 | $ 66,000 |
Estimated amortization expense- 2021 |  | 425,000 |  |
Estimated amortization expense- 2022 |  | 390,000 |  |
Estimated amortization expense - 2023 |  | 362,000 |  |
Estimated amortization expense - 2024 |  | 336,000 |  |
Estimated amortization expense - 2025 |  | $ 315,000 |  |
Weighted average remaining amortization period for acquired intangible assets |  | 17 years 4 months 24 days |  | 17 years 6 months
Research and development costs |  | $ 1,889,000 | $ 1,749,000 |
Antidilutive options outstanding excluded from diluted EPS computations |  | 40,000 | 0 |
Stock-based compensation expense |  | $ 104,000 | $ 17,000 |
Foreign Currency Transaction Gain (Loss), before Tax |  | $ 0 | $ 0 |
Stock-based compensation costs, effect on EPS |  | $ 0.01 | $ 0.00 |
Number of Operating Segments |  | 1 |  |
Cost of Goods and Services Sold |  | $ 12,481,000 | $ 14,767,000 |
Operating Lease, Liability | $ 7,700,000 |  |  |
Operating Lease, Right-of-Use Asset | $ 7,700,000 | 7,390,000 |  | $ 7,395,000
Package of practical expedients | true |  |  |
Selling, General and Administrative Expenses [Member] |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Advertising and promotion costs |  | 343,000 | 514,000 |
Sales revenue, net [Member] | Shipping and Handling [Member] |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Cost of Goods and Services Sold |  | 221,000 | 260,000 |
Cost of sales [Member] |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Research and development costs |  | 1,889,000 | 1,749,000 |
Cost of sales [Member] | Shipping and Handling [Member] |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Cost of Goods and Services Sold |  | 106,000 | $ 112,000 |
Allowance for doubtful accounts current |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Valuation allowances and reserves, balance |  | $ 326,000 |  | $ 326,000
Trade name |  |  |  |
Significant Accounting Policies [Line Items] |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  | 20 years |  |
Impairment of intangible asset |  | $ 1,852,000 |  |

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