Income Taxes - Additional Disclosures (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Operating Loss Carryforwards [Line Items]
Income tax expense (benefit) allocated to discontinued operations		$ 100	$ (15,100)	$ (16,400)
Decrease to the valuation allowance		3,200
Gain on restructured notes receivable	$ (3,000)	3,048	0	0
Undistributed losses of foreign subsidiaries	20,600	20,600
Undistributed earnings of foreign subsidiaries, estimated taxes recognized upon distribution	1,000	1,000
Unrecognized tax benefits	6,530	6,530	$ 6,058	$ 6,058	$ 4,402
State Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforward	174,000	174,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforward	34,800	34,800
Tax credit carryforward	$ 3,100	$ 3,100