Related Party Transactions - W. Mark Humphrey (Details) - W. Mark Humphrey - USD ($)  | 
12 Months Ended | |||
|---|---|---|---|---|
Jun. 01, 2015  | 
Sep. 30, 2018  | 
Sep. 30, 2017  | 
Sep. 30, 2016  | 
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| Related Party Transaction [Line Items] | ||||
| Consulting services and covenant period | 1 year | |||
| Cash in a lump sum | $ 100,000 | |||
| Payments for services and covenants | $ 350,000 | |||
| Expense under separation and consulting agreement | $ 0 | $ 0 | $ 238,000 | |
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- Definition Related Party Transaction, Period After Closing No definition available. 
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- Definition Amount of transactions with related party during the financial reporting period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party. 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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- Definition Amount of postemployment benefit liabilities classified as other. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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