Summary of Significant Accounting Policies - Changes in Product Warranty Accrual (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Product Warranty Liability [Line Items]
Product warranty term	12 months
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Beginning Balance	$ 1,336	$ 1,691	$ 1,523
Accruals for warranties issued during the period	2,274	1,318	1,328
Settlements made during the period	(1,909)	(1,790)	(1,366)
Ending Balance	1,870	1,336	1,691
Germane Systems, LC
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Warranty assumed from CES	169	0	0
Themis
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Warranty assumed from CES	0	117	0
CES Creative Electronic Systems S.A.
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Warranty assumed from CES	0	0	176
Delta
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Warranty assumed from CES	$ 0	$ 0	$ 30

Product Warranty, Term

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Topic 460
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-Section 50
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Amount of increase in the standard and extended product warranty accrual from a business acquisition.

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- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 460
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-Section 50
-Paragraph 8
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- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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