CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' DEFICIT (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid in Capital [Member]	Accumulated other comprehensive income [Member]	Accumulated Deficit [Member]	Total
Balance at beginning at Sep. 30, 2017	$ 2	$ 323,429	$ 53,145	$ (378,905)	$ (2,329)
Balance at beginning (in shares) at Sep. 30, 2017	20,402,602
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments			124		124
Actuarial losses on pension plan			(2,046)		(2,046)
Shares issued on exercise of warrants		1			1
Shares issued on exercise of warrants (in shares)	50
Shares issued upon cashless exercise of RSUs		(1,043)			(1,043)
Shares issued upon cashless exercise of RSUs (in shares)	445,723
Stock-based compensation expense		783			783
Reclassification of RSUs to derivative liability due to modification		(1,482)			(1,482)
Net loss				(4,155)	(4,155)
Balance at ending at Dec. 31, 2017	$ 2	321,688	51,223	(383,060)	(10,147)
Balance at ending (in shares) at Dec. 31, 2017	20,848,375
Balance at beginning at Sep. 30, 2017	$ 2	323,429	53,145	(378,905)	(2,329)
Balance at beginning (in shares) at Sep. 30, 2017	20,402,602
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss					(498)
Balance at ending at Mar. 31, 2018	$ 2	325,492	52,823	(383,558)	(5,241)
Balance at ending (in shares) at Mar. 31, 2018	20,860,591
Balance at beginning at Dec. 31, 2017	$ 2	321,688	51,223	(383,060)	(10,147)
Balance at beginning (in shares) at Dec. 31, 2017	20,848,375
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments			298		298
Actuarial losses on pension plan			1,302		1,302
Change in fair value of hedging instrument
Reclassification of gain on hedging instrument to comprehensive income
Shares issued upon cashless exercise of RSUs (in shares)	12,216
Stock-based compensation expense		956			956
Reclassification of RSUs from derivative liability due to stockholder approval of Second Incentive Plan		2,848			2,848
Net loss				(498)	(498)
Balance at ending at Mar. 31, 2018	$ 2	325,492	52,823	(383,558)	(5,241)
Balance at ending (in shares) at Mar. 31, 2018	20,860,591
Balance at beginning at Sep. 30, 2018	$ 2	328,452	58,580	(399,501)	$ (12,467)
Balance at beginning (in shares) at Sep. 30, 2018	20,860,591				20,860,591
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments			(6)		$ (6)
Actuarial losses on pension plan			(2,825)		(2,825)
Change in fair value of hedging instrument			2,601		2,601
Reclassification of gain on hedging instrument to comprehensive income			(2,362)		(2,362)
Shares issued upon cashless exercise of RSUs		(4)			(4)
Shares issued upon cashless exercise of RSUs (in shares)	9,806
Stock-based compensation expense		1,407			1,407
Net loss				(4,729)	(4,729)
Balance at ending at Dec. 31, 2018	$ 2	329,855	55,988	(404,230)	(18,385)
Balance at ending (in shares) at Dec. 31, 2018	20,870,397
Balance at beginning at Sep. 30, 2018	$ 2	328,452	58,580	(399,501)	$ (12,467)
Balance at beginning (in shares) at Sep. 30, 2018	20,860,591				20,860,591
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments					$ (490)
Net loss					(4,953)
Balance at ending at Mar. 31, 2019	$ 2	340,210	55,747	(409,183)	$ (13,224)
Balance at ending (in shares) at Mar. 31, 2019	22,193,955				22,193,955
Balance at beginning at Dec. 31, 2018	$ 2	329,855	55,988	(404,230)	$ (18,385)
Balance at beginning (in shares) at Dec. 31, 2018	20,870,397
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustments			(484)		(484)
Actuarial losses on pension plan			893		893
Change in fair value of hedging instrument			(2,123)		(2,123)
Reclassification of gain on hedging instrument to comprehensive income			1,473		1,473
Shares issued on earnout		8,616			8,616
Shares issued on earnout (in shares)	1,323,558
Stock-based compensation expense		1,739			1,739
Net loss				(4,953)	(4,953)
Balance at ending at Mar. 31, 2019	$ 2	$ 340,210	$ 55,747	$ (409,183)	$ (13,224)
Balance at ending (in shares) at Mar. 31, 2019	22,193,955				22,193,955