Detail of Selected Balance Sheet Accounts

3 Months Ended

Dec. 31, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Detail of Selected Balance Sheet Accounts

Detail of Selected Balance Sheet Accounts

Allowance for Doubtful Accounts

Activity in our allowance for doubtful accounts consisted of the following (in thousands):

	Three months ended December 31,
	2019			2018
Balance at beginning of period	$	301		$	157
Bad debt expense	42			27
Uncollectible accounts written off, net of recoveries	(10		)	(42		)
Change due to foreign currency translation	13			(3		)
Balance at end of period	$	346		$	139

Inventories

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

	December 31, 2019		September 30, 2019
Raw materials, parts and sub-assemblies, net	$	31,526	$	28,102
Work-in-progress	922		1,100
Total inventories	$	32,448	$	29,202

Accrued Product Warranty

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

	Three months ended December 31,
	2019			2018
Balance at beginning of period	$	2,946		$	2,604
Increase in warranty expense	843			746
Deduction for warranty charges	(645		)	(604		)
Change due to foreign currency translation	18			(14		)
Balance at end of period	$	3,162		$	2,732