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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Quality System remediation costs.

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Intangible Assets - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	May 17, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ 849	$ 939	$ 2,732	$ 2,843
Estimated amortization expense for intangible assets remainder of fiscal year 2018		844		844
2019		3,333		3,333
2020		3,170		3,170
2021		2,561		2,561
2022		2,182		2,182
2023		2,170		2,170
Goodwill impairment charge			6,628		6,628
Quality System remediation costs		$ 100		$ 900
Magellan [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment charge			$ 6,628		$ 6,628
Revenues [Member] \| Product Concentration Risk [Member] \| LeadCare Plus and LeadCare Ultra Systems [Member]
Finite-Lived Intangible Assets [Line Items]
Concentration risk percentage	10.00%