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Employee Benefits Plans - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2017
Retirement Benefits [Abstract] |  |  |
Benefit plan period | 180 months |  |
Weighted-average discount rate | 4.08% | 4.08% |
Additional liability recorded | $ 720 |  |
Matching contribution (as a percent) (up to) | 4.00% |  |
Contribution to plan | $ 380 | $ 342 | $ 445
Contribution to profit sharing plan | $ 0 | $ 0 | $ 378

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- Definition Defined Benefit Plan, Plan Period + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement. + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + 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 (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan. + 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 (a)(7) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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