Supplementary Balance Sheet Information

12 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Supplementary Balance Sheet Information

11.    Supplementary Balance Sheet Information

The following is a summary of accounts receivable at September 30, 2023 and 2022 (in thousands):

	September 30,
	2023		2022
Accounts receivable	$	164,592	$	168,920
Less allowance for expected credit losses		(8,057)		(5,162)
Accounts receivable, net	$	156,535	$	163,758

The allowance for expected credit losses for the fiscal years ended September 30, 2023, 2022 and 2021 is as follows (in thousands):

	Year Ended September 30,
	2023		2022		2021
Balance at beginning of period	$	5,162	$	4,318	$	7,146
Provisions		8,849		3,536		3,445
Payments received		(5,884)		(2,278)		(5,481)
Write-offs and adjustments		(70)		(414)		(792)
Balance at end of period	$	8,057	$	5,162	$	4,318

The following is a summary of inventories at September 30, 2023 and 2022 (in thousands):

	September 30,
	2023		2022
Raw materials and purchased parts	$	59,861	$	39,685
Work-in-process		11,400		4,816
Finished goods		56,937		41,043
Total inventories	$	128,198	$	85,544

The activity for excess and obsolete inventory reserves is as follows for the fiscal years ended September 30, 2023, 2022 and 2021 (in thousands):

	Year Ended September 30,
	2023		2022		2021
Balance at beginning of period	$	4,082	$	3,681	$	3,136
Provisions		3,324		1,752		1,522
Inventory disposals and adjustments		(2,415)		(1,351)		(977)
Balance at end of period	$	4,991	$	4,082	$	3,681

The activity for valuation allowance for deferred tax assets is as follows for the fiscal years ended September 30, 2023, 2022 and 2021 (in thousands):

	Year Ended September 30,
	2023		2022		2021
Balance at beginning of period	$	5,927	$	8,592	$	10,623
Charge to income tax provision (benefit)		1,137		1,337		(3,247)
Charged to other accounts		1,284		(4,002)		1,216
Balance at end of period	$	8,348	$	5,927	$	8,592

The following is a summary of product warranty and retrofit activity on a gross basis for the fiscal years ended September 30, 2023, 2022 and 2021 (in thousands):

	Year Ended September 30,
	2023		2022		2021
Balance at beginning of period	$	2,890	$	2,330	$	2,211
Adjustments for acquisitions and divestitures		2,475		254		—
Accruals for warranties during the year		8,198		2,438		2,300
Costs incurred during the year		(3,340)		(2,132)		(2,181)
Balance at end of period	$	10,223	$	2,890	$	2,330