CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Ordinary Shares [Member]	Additional paid in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Beginning balance at Mar. 31, 2018	$ (14,631)	$ 253,934	$ 23,708	$ (16,634)	$ (275,639)
Beginning balance, Shares at Mar. 31, 2018		45,646,424
Issue of shares, net of issue costs, Amount	113,723	$ 113,723
Issue of shares, net of issue costs, Shares		19,085,068
Issue of shares upon exercise of incentive share options and vesting of RSU's, Amount	22	$ 22
Issue of shares upon exercise of incentive share options and vesting of RSU's, Shares		241,060
Net loss	(78,792)				(78,792)
Change in the fair value of the effective portion of foreign currency cash flow hedges	(320)			(320)
Change in unrealized gain on short-term investments	416			416
Foreign currency gain (loss) on:
Long-term investment nature intra-entity balances	10,848			10,848
Retranslation of foreign entities	(10,294)			(10,294)
Provision for pension benefit obligation	107			107
Other comprehensive loss	757			757
Stock-based compensation	3,576		3,576
Ending balance at Dec. 31, 2018	24,655	$ 367,679	27,284	(15,877)	(354,431)
Ending balance, Shares at Dec. 31, 2018		64,972,552
Beginning balance at Sep. 30, 2018	(14,736)	$ 303,176	26,211	(15,946)	(328,177)
Beginning balance, Shares at Sep. 30, 2018		54,229,503
Issue of shares, net of issue costs, Amount	64,503	$ 64,503
Issue of shares, net of issue costs, Shares		10,615,385
Issue of shares upon exercise of incentive share options and vesting of RSU's, Shares		127,664
Net loss	(26,254)				(26,254)
Change in the fair value of the effective portion of foreign currency cash flow hedges	41			41
Change in unrealized gain on short-term investments	169			169
Foreign currency gain (loss) on:
Long-term investment nature intra-entity balances	3,399			3,399
Retranslation of foreign entities	(3,575)			(3,575)
Provision for pension benefit obligation	35			35
Other comprehensive loss	69			69
Stock-based compensation	1,073		1,073
Ending balance at Dec. 31, 2018	24,655	$ 367,679	27,284	(15,877)	(354,431)
Ending balance, Shares at Dec. 31, 2018		64,972,552
Beginning balance at Mar. 31, 2019	$ 1,714	$ 368,958	28,665	(14,884)	(381,025)
Beginning balance, Shares at Mar. 31, 2019	65,900,447	65,900,447
Issue of shares, net of issue costs, Amount	$ 90,373	$ 90,373
Issue of shares, net of issue costs, Shares		13,800,000
Issue of shares upon exercise of incentive share options and vesting of RSU's, Amount	355	$ 355
Issue of shares upon exercise of incentive share options and vesting of RSU's, Shares		556,499
Net loss	(78,046)				(78,046)
Change in the fair value of the effective portion of foreign currency cash flow hedges	209			209
Change in unrealized gain on short-term investments	342			342
Foreign currency gain (loss) on:
Long-term investment nature intra-entity balances	2,972			2,972
Retranslation of foreign entities	(3,743)			(3,743)
Provision for pension benefit obligation	144			144
Other comprehensive loss	(76)			(76)
Stock-based compensation	3,375		3,375
Cumulative effect of accounting changes	363				363
Ending balance at Dec. 31, 2019	$ 18,058	$ 459,686	32,040	(14,960)	(458,708)
Ending balance, Shares at Dec. 31, 2019	80,256,946	80,256,946
Beginning balance at Sep. 30, 2019	$ (46,941)	$ 369,335	30,844	(15,897)	(431,223)
Beginning balance, Shares at Sep. 30, 2019		66,366,706
Issue of shares, net of issue costs, Amount	90,373	$ 90,373
Issue of shares, net of issue costs, Shares		13,800,000
Issue of shares upon exercise of incentive share options and vesting of RSU's, Amount	(22)	$ (22)
Issue of shares upon exercise of incentive share options and vesting of RSU's, Shares		90,240
Net loss	(27,485)				(27,485)
Change in the fair value of the effective portion of foreign currency cash flow hedges	487			487
Change in unrealized gain on short-term investments	148			148
Foreign currency gain (loss) on:
Long-term investment nature intra-entity balances	(7,435)			(7,435)
Retranslation of foreign entities	7,689			7,689
Provision for pension benefit obligation	48			48
Other comprehensive loss	937			937
Stock-based compensation	1,196		1,196
Ending balance at Dec. 31, 2019	$ 18,058	$ 459,686	$ 32,040	$ (14,960)	$ (458,708)
Ending balance, Shares at Dec. 31, 2019	80,256,946	80,256,946