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Income Taxes - Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2014
Effective Income Tax Rate Reconciliation [Line Items] |  |  |
Income Tax Reconciliation, Income Tax Expense (Benefit), at Federal Statutory Income Tax Rate | $ 8,316 | $ 6,139 | $ 2,195
Income Tax Expense (Benefit) | (97,117) | 661 | 748
Increase Resulting From [Member] |  |  |
Effective Income Tax Rate Reconciliation [Line Items] |  |  |
Alternative Minimum Tax | 0 | 417 | 0
Income Tax Reconciliation, Nondeductible Expense | 1,557 | 753 | 563
Long-lived Assets | 0 | 69 | 0
Income Tax Reconciliation, State and Local Income Taxes | 1,105 | 937 | 544
Contingent Tax Liabilities | 0 | 51 | 0
Effective Income Tax Rate Rec Other | 0 | 54 | 0
Decrease Resulting From [Member] |  |  |
Effective Income Tax Rate Reconciliation [Line Items] |  |  |
Contingent Tax Liabilities | (96) | 0 | (1)
Effective Income Tax Rate Rec Other | 988 | 0 | (6)
Change in valuation allowance | (108,987) | (7,034) | (2,547)
Valuation Allowance Adjustment Acquisition | $ 0 | $ (725) | $ 0

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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=6907707&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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