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Income Taxes - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended |
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Sep. 30, 2017 | Sep. 30, 2016
Income Tax Disclosure [Abstract] |  |
Liability for uncertain tax positions | $ 104 | $ 105
Returns open to examination, minimum (years) | 3 years |
Returns open to examination, maximum (years) | 5 years |
Returns open to examination, state impact of federal changes, maximum (years) | 2 years |

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- Definition Amount recognized for uncertainty in income taxes classified as noncurrent. + 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 210.5-02.24) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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