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Retirement Benefit Plans - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018
Retirement Benefits [Abstract] |  |
Employer contributions | $ 403 |
Plan funded percentage | 89.00% |
Employer matching contribution percentage of employees' gross pay | 100.00% |
Percentage of eligible compensation of deferral contribution, minimum | 1.00% |
Percentage of eligible compensation | 80.00% |
Percentage of eligible compensation of deferral contribution, maximum | 6.00% |
Matching contribution expense for defined contribution plan | $ 470 | $ 475

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- Definition Percentage of eligible compensation of deferral contribution, maximum. + References No definition available. + Details
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- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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