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v3.21.2

Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2021 USD ($) customer shares | Sep. 30, 2020 USD ($) customer shares
Accounting Policies [Line Items] |  |
Allowance for doubtful accounts | $ 167 | $ 249
Accounts receivable, allowance for credit loss, recovery | 9 |
Accounts receivable, written off |  | 263
Bad debt benefit | $ 91 | $ 80
Percentage of inventory estimated using LIFO method | 39.00% | 47.00%
Reserve for obsolete and excess inventory | $ 3,444 | $ 3,676
Depreciation expense | $ 6,651 | $ 5,883
Anti-dilutive weighted-average common shares excluded from calculation of diluted earnings per share (in shares) | shares | 412,000 | 207,000
Restricted shares |  |
Accounting Policies [Line Items] |  |
Anti-dilutive weighted-average common shares excluded from calculation of diluted earnings per share (in shares) | shares | 0 | 0
Minimum |  |
Accounting Policies [Line Items] |  |
Finite-lived intangible asset, useful life (in years) | 1 year |
Maximum |  |
Accounting Policies [Line Items] |  |
Finite-lived intangible asset, useful life (in years) | 10 years |
Building and Building Improvements | Minimum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 5 years |
Building and Building Improvements | Maximum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 40 years |
Machinery and Equipment | Minimum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 3 years |
Machinery and Equipment | Maximum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 20 years |
Computer Software | Minimum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 3 years |
Computer Software | Maximum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 7 years |
Leasehold Improvements | Minimum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 6 years |
Leasehold Improvements | Maximum |  |
Accounting Policies [Line Items] |  |
Property, plant and equipment, useful life (in years) | 15 years |
Customer Concentration Risk | Sales Revenue, Net |  |
Accounting Policies [Line Items] |  |
Number of major customers | customer | 2 | 1
Customer Concentration Risk | Sales Revenue, Net | Total Customers and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk | 38.00% | 49.00%
Number of major customers | customer | 3 | 4
Customer Concentration Risk | Sales Revenue, Net | Major Customer One and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk | 17.00% | 16.00%
Customer Concentration Risk | Sales Revenue, Net | Major Customer Two and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk | 11.00% | 13.00%
Customer Concentration Risk | Sales Revenue, Net | Major Customer Three and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk | 10.00% | 10.00%
Customer Concentration Risk | Sales Revenue, Net | Major Customer Four and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk |  | 10.00%
Customer Concentration Risk | Sales Revenue, Net | Customer One |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk |  | 10.00%
Customer Concentration Risk | Sales Revenue, Net | Two Largest Customers |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk | 20.00% |
Customer Concentration Risk | Accounts Receivable |  |
Accounting Policies [Line Items] |  |
Number of major customers | customer |  | 1
Customer Concentration Risk | Accounts Receivable | Total Customers and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Number of major customers | customer | 1 | 3
Customer Concentration Risk | Accounts Receivable | Major Customer One and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk | 17.00% | 13.00%
Customer Concentration Risk | Accounts Receivable | Major Customer Two and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk |  | 13.00%
Customer Concentration Risk | Accounts Receivable | Major Customer Three and Their Subcontractors |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk |  | 12.00%
Customer Concentration Risk | Accounts Receivable | Customer One |  |
Accounting Policies [Line Items] |  |
Percentage of concentration risk |  | 11.00%

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