Supplementary Balance Sheet Information

12 Months Ended

Sep. 30, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Supplementary Balance Sheet Information

9.    Supplementary Balance Sheet Information

The following is a summary of accounts receivable at September 30, 2019 and 2018 (in thousands):

	September 30,		September 30,
	2019		2018
Accounts receivable	$	169,317	$	126,350
Less allowance for doubtful accounts		(3,644)		(1,113)
Less allowance for sales returns		(71)		(45)
Accounts receivable, net	$	165,602	$	125,192

The allowance for doubtful accounts activity for the fiscal years ended September 30, 2019, 2018 and 2017 is as follows (in thousands):

	Balance at				Reversals of		Write-		Balance at
	Beginning of				Bad Debt		offs and		End of
Description	Period		Provisions		Expense		Adjustments		Period
2019 Allowance for doubtful accounts	$	1,113	$	3,405	$	(693)	$	(181)	$	3,644
2018 Allowance for doubtful accounts		1,381		708		(724)		(252)		1,113
2017 Allowance for doubtful accounts		1,543		—		(131)		(31)		1,381

The allowance for sales returns activity for the fiscal years ended September 30, 2019, 2018 and 2017 is as follows (in thousands):

	Balance at				Write-		Balance at
	Beginning of				offs and		End of
Description	Period		Provisions		Adjustments		Period
2019 Allowance for sales returns	$	45	$	26	$	—	$	71
2018 Allowance for sales returns		81		(36)		—		45
2017 Allowance for sales returns		101		(20)		—		81

The following is a summary of inventories at September 30, 2019 and 2018 (in thousands):

	September 30,		September 30,
	2019		2018
Inventories
Raw materials and purchased parts	$	67,176	$	57,527
Work-in-process		13,684		19,547
Finished goods		18,585		19,912
Total inventories	$	99,445	$	96,986

The activity for excess and obsolete inventory reserves is as follows for the fiscal years ended September 30, 2019, 2018 and 2017 (in thousands):

	Balance at				Inventory		Balance at
	Beginning of				Disposals and		End of
Description	Period			Provisions	Adjustments		Period
2019 Reserves for excess and obsolete inventory	$	14,953	$	5,865	$	(4,520)	$	16,298
2018 Reserves for excess and obsolete inventory		17,734		4,455		(7,236)		14,953
2017 Reserves for excess and obsolete inventory		19,663		4,858		(6,787)		17,734

The activity for valuation allowance for deferred tax assets is as follows for the fiscal years ended September 30, 2019, 2018 and 2017 (in thousands):

	Balance at						Balance at
	Beginning of		Charged to		Charged to		End of
Description	Period		Provisions		Other Accounts		Period
2019 Valuation allowance for deferred tax assets	$	18,581	$	(3,475)	$	987	$	16,093
2018 Valuation allowance for deferred tax assets		92,297		(72,842)		(874)		18,581
2017 Valuation allowance for deferred tax assets		104,802		(10,881)		(1,624)		92,297

The Company establishes reserves for estimated cost of product warranties based on historical information. Product warranty reserves are recorded at the time product revenue is recognized, and retrofit accruals are recorded at the time retrofit programs are established. The Company’s warranty obligation is affected by product failure rates, utilization levels, material usage, service delivery costs incurred in correcting a product failure and supplier warranties on parts delivered to the Company. The following is a summary of product warranty and retrofit activity on a gross basis,

excluding amounts related to discontinued operations, for the fiscal years ended September 30, 2019, 2018 and 2017 (in thousands):

	Amount
Balance at September 30, 2016	$	4,159
Accruals for warranties during the year		6,683
Costs incurred during the year		(5,363)
Balance at September 30, 2017		5,479
Accruals for warranties during the year		5,209
Costs incurred during the year		(4,348)
Balance at September 30, 2018		6,340
Accruals for warranties during the year		8,688
Costs incurred during the year		(7,853)
Balance at September 30, 2019	$	7,175