Accrued Expenses and Other Current Liabilities (Income and Other Taxes) (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax (expense) benefit	$ (32)	$ (19)	$ 8	$ (120)	$ 8	$ (175)	$ 155	$ (2)	$ (163)	$ (14)	$ 2,191	$ 24,600
Tax effect of gain (loss) from disposal of discontinued operations									$ 0	$ 24	$ (26,500)