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Income Taxes - Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	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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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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