Detail of Selected Balance Sheet Accounts (Tables)

6 Months Ended

Mar. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Activity in Allowance for Doubtful Accounts Receivable

Activity in our allowance for credit losses consisted of the following (in thousands):

	Three months ended March 31,				Six months ended March 31,
	2022		2021		2022		2021
Balance at beginning of period	$	411	$	493	$	333	$	510
Bad debt expense (recovery), net	353		(113)		445		(132)
Uncollectible accounts written off, net of recoveries	(57)		—		(71)		(10)
Change due to foreign currency translation	(4)		2		(4)		14
Balance at end of period	$	703	$	382	$	703	$	382

Components of Inventories

The components of inventories are summarized below (in thousands):

	March 31, 2022		September 30, 2021
Raw materials, parts and sub-assemblies, net	$	42,282	$	28,688
Work-in-progress	1,403		1,147
Total inventories	$	43,685	$	29,835

Activity in Product Warranty Accrual

Activity in our product warranty accrual consisted of the following (in thousands):

	Three months ended March 31,				Six months ended March 31,
	2022		2021		2022		2021
Balance at beginning of period	$	2,443	$	2,675	$	2,531	$	2,771
Increase to warranty expense	323		395		616		1,053
Deduction for warranty charges	(421)		(609)		(803)		(1,388)
Change due to foreign currency translation	2		6		3		31
Balance at end of period	$	2,347	$	2,467	$	2,347	$	2,467