Detail of Selected Balance Sheet Accounts - Activity in Allowance for Doubtful Accounts Receivable (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 510	$ 301
Bad debt expense (recovery)	(19)	42
Uncollectible accounts written off, net of recoveries	(10)	(10)
Change due to foreign currency translation	12	13
Balance at end of period	$ 493	$ 346