Segment Information - Revenues by Geographic Location (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Oct. 31, 2020	Jul. 31, 2020	Apr. 30, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Schedule Of Revenues By Geographic Area [Line Items]
Revenues	$ 16,999	$ 18,728	$ 18,880	$ 16,264	$ 11,041	$ 22,712	$ 9,216	$ 17,783	$ 70,871	$ 60,752	$ 89,437
UNITED STATES
Schedule Of Revenues By Geographic Area [Line Items]
Revenues									67,750	56,211	50,953
SOUTH KOREA
Schedule Of Revenues By Geographic Area [Line Items]
Revenues									2,059	2,686	36,279
ENGLAND
Schedule Of Revenues By Geographic Area [Line Items]
Revenues									25	1,496	387
GERMANY
Schedule Of Revenues By Geographic Area [Line Items]
Revenues									414	$ 359	1,795
CANADA
Schedule Of Revenues By Geographic Area [Line Items]
Revenues											$ 23
SWITZERLAND
Schedule Of Revenues By Geographic Area [Line Items]
Revenues									$ 623