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Long-Term Debt - Additional Information (Details) - Frost Bank Credit Agreement - USD ($) |  | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Oct. 25, 2017 | Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2015 | May 04, 2015 | Mar. 02, 2011
Debt Instrument [Line Items] |  |  |  |  |  |
Total long-term debt outstanding |  | $ 0 | $ 0 | $ 0 |  |
Line of credit borrowing capacity |  | 24,100,000 |  |  |  | $ 50,000,000
Credit agreement borrowing availability |  | 23,800,000 |  |  | $ 30,000,000 |
Outstanding letters of credit |  | $ 300,000 |  |  |  |
Credit agreement expiration date |  | May 04, 2018 |  |  |  |
Prime Rate |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Marginal interest rate |  | 4.25% |  |  |  |
Certain Accounts Receivable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Borrowing base as percentage of assets |  |  |  |  | 80.00% |
Certain Notes Receivable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Borrowing base as percentage of assets |  |  |  |  | 50.00% |
Maximum amount of borrowing based upon assets |  |  |  |  | $ 10,000,000 |
Certain Inventories |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Borrowing base as percentage of assets |  |  |  |  | 25.00% |
New Agreement |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Credit agreement date |  | Mar. 02, 2011 |  |  |  |
Subsequent Event | Second Amendment |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Credit agreement expiration date | Apr. 30, 2019 |  |  |  |  |
Unencumbered liquid asset value | $ 10,000,000 |  |  |  |  |
Subsequent Event | Second Amendment | Certain Accounts Receivable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Borrowing base as percentage of assets | 80.00% |  |  |  |  |
Subsequent Event | Second Amendment | Certain Notes Receivable |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Borrowing base as percentage of assets | 50.00% |  |  |  |  |
Maximum amount of borrowing based upon assets | $ 10,000,000 |  |  |  |  |
Subsequent Event | Second Amendment | Certain Inventories |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Borrowing base as percentage of assets | 25.00% |  |  |  |  |
Maximum amount of borrowing based upon assets | $ 20,000,000 |  |  |  |  |

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- Definition Maximum amount of line of credit facility borrowing based upon assets. + References No definition available. + Details
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1314-112600 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=28361426&loc=d3e1336-112600 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Line-of-Credit Arrangement -URI http://asc.fasb.org/extlink&oid=6517033 + Details
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