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Income Taxes - Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2015
Effective Income Tax Rate Reconciliation [Line Items] |  |  |
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate | $ 6,582 | $ 8,316 | $ 6,139
Income Tax Expense (Benefit) | 5,211 | (97,117) | 661
Increase Resulting From [Member] |  |  |
Effective Income Tax Rate Reconciliation [Line Items] |  |  |
Alternative Minimum Tax | 0 | 0 | 417
Income Tax Reconciliation, Nondeductible Expense | 966 | 1,557 | 753
Long-lived Assets | 0 | 0 | 69
Income Tax Reconciliation, State and Local Income Taxes | 1,003 | 1,105 | 937
Contingent Tax Liabilities | 0 | 0 | 51
Effective Income Tax Rate Rec Other | 17 | 0 | 54
Change in valuation allowance | 142 |  |
Decrease Resulting From [Member] |  |  |
Effective Income Tax Rate Reconciliation [Line Items] |  |  |
Contingent Tax Liabilities | (3,499) | (96) | 0
Effective Income Tax Rate Rec Other | 0 | 988 | 0
Change in valuation allowance | 0 | (108,987) | (7,034)
Valuation Allowance Adjustment Acquisition | $ 0 | $ 0 | $ (725)

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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a),(b) -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32639-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(h)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Income Tax Expense (or Benefit) -URI http://asc.fasb.org/extlink&oid=6515339 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32698-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=75116654&loc=d3e32123-109318 + Details
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