The aggregate direct transaction costs incurred during the reporting period.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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Amount of restructuring charges, remediation cost, and asset impairment loss.

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Impairment, Restructuring and Other Charges (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Dec. 31, 2017	Sep. 30, 2021	Sep. 30, 2020
Impairment, Restructuring and Other Charges
Impairment charges			$ 552
Employee termination costs		$ 336	3,883
Mexico transaction costs			2,692
Facility closures/consolidation		(61)	1,272
Legal costs (recoveries), net	$ 12,500	2,235	(40)
Total expensed		2,510	8,359
Other operational efficiency activities
Impairment, Restructuring and Other Charges
Net benefit recognized related to reimbursement from insurance		(2,200)
Employee termination costs		300	1,400
Total expensed		2,500
Security Division
Impairment, Restructuring and Other Charges
Impairment charges			552
Employee termination costs		336	3,737
Mexico transaction costs			2,692
Facility closures/consolidation		(61)	1,272
Total expensed		275	8,253
Optoelectronics and Manufacturing Division
Impairment, Restructuring and Other Charges
Employee termination costs			146
Total expensed			146
Corporate.
Impairment, Restructuring and Other Charges
Legal costs (recoveries), net		2,235	(40)
Total expensed		$ 2,235	(40)
Turnkey Screening Program \| Other operational efficiency activities
Impairment, Restructuring and Other Charges
Other Restructuring charges			100
Turnkey Screening Program \| Security Division
Impairment, Restructuring and Other Charges
Restructuring Charges			(6,900)
Employee termination costs			2,500
Direct transaction costs			2,700
Impairment of right-of-use asset			600
Other Restructuring charges			$ 1,100