Basis of Presentation and Significant Accounting Policies - Effect of New Accounting Pronouncement (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018	Sep. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by (used in) operating activities	$ (646)	$ (14,622)
Effect of Exchange Rate Changes on Cash, Cash Equivalents and Restricted Cash	(662)	453
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash	(1,518)	(13,152)
Cash, Cash Equivalents and Restricted Cash, Beginning of Period	60,978	62,609	$ 62,496	$ 75,761
Cash, Cash Equivalents and Restricted Cash, End of Period	$ 60,978	62,609	$ 62,496	75,761
As reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net cash provided by (used in) operating activities		263
Effect of Exchange Rate Changes on Cash, Cash Equivalents and Restricted Cash		295
Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash		1,575
Cash, Cash Equivalents and Restricted Cash, Beginning of Period		52,696		51,121
Cash, Cash Equivalents and Restricted Cash, End of Period		$ 52,696		$ 51,121