Other Balance Sheet Information (Tables)

6 Months Ended

Mar. 31, 2020

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Summary of Accounts Receivable

The following is a summary of accounts receivable at March 31, 2020 and September 30, 2019 (in thousands):

	March 31,		September 30,
	2020		2019
Accounts receivable	$	183,324	$	169,317
Less allowance for doubtful accounts		(4,225)		(3,644)
Less allowance for sales returns		(85)		(71)
Accounts receivable, net	$	179,014	$	165,602

Summary of Inventories

The following is a summary of inventories at March 31, 2020 and September 30, 2019 (in thousands):

	March 31,		September 30,
	2020		2019
Inventories
Raw materials and purchased parts	$	73,473	$	67,176
Work-in-process		13,443		13,684
Finished goods		20,783		18,585
Total inventories	$	107,699	$	99,445

Product Warranty and Retrofit Activity on Gross Basis

The following is a summary of product warranty and retrofit activity on a gross basis for the three and six months ended March 31, 2020 and 2019 (in thousands):

Activity -Three Months Ended March 31, 2020
Balance						Balance
December 31,						March 31,
2019		Accruals		Costs Incurred		2020
$	7,493	$	2,174	$	(1,757)	$	7,910
Activity -Three Months Ended March 31, 2019
Balance						Balance
December 31,						March 31,
2018		Accruals		Costs Incurred		2019
$	6,851	$	1,807	$	(1,456)	$	7,202
Activity -Six Months Ended March 31, 2020
Balance						Balance
September 30,						March 31,
2019		Accruals		Costs Incurred		2020
$	7,175	$	4,653	$	(3,918)	$	7,910
Activity -Six Months Ended March 31, 2019
Balance						Balance
September 30,						March 31,
2018		Accruals		Costs Incurred		2019
$	6,340	$	4,161	$	(3,299)	$	7,202