Segment Information - Operations and Identifiable Assets (Details) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($) customer	Mar. 31, 2018 USD ($) segment	Mar. 31, 2017 USD ($)	Jun. 30, 2017 USD ($)
Operations and identifiable assets by industry segment
Number of identifiable industry segments \| segment			3
Total revenues	$ 267,299	$ 245,146	$ 801,960	$ 708,549
Operating income (loss)	7,743	$ 19,694	45,284	$ 30,486
Segments assets	1,396,031		$ 1,396,031		$ 1,230,087
SAT in Mexico \| Revenue \| Customer
Operations and identifiable assets by industry segment
Number of major customers \| customer		1
Percentage of benchmark derived from specified source		12.00%	11.00%	12.00%
Operating Segments \| Security Division
Operations and identifiable assets by industry segment
Total revenues	170,270	$ 144,824	$ 504,784	$ 408,037
Operating income (loss)	21,028	18,287	66,192	36,767
Segments assets	975,807		975,807		785,230
Operating Segments \| Healthcare Division
Operations and identifiable assets by industry segment
Total revenues	43,758	49,667	141,793	146,427
Operating income (loss)	(8,425)	936	(6,975)	(1,527)
Segments assets	164,911		164,911		186,021
Operating Segments \| Optoelectronics and Manufacturing division
Operations and identifiable assets by industry segment
Total revenues	66,212	58,309	189,024	175,864
Operating income (loss)	6,547	5,974	16,224	16,149
Segments assets	225,672		225,672		196,567
Corporate
Operations and identifiable assets by industry segment
Operating income (loss)	(10,730)	(6,067)	(28,601)	(21,882)
Segments assets	33,887		33,887		64,959
Intersegment Eliminations
Operations and identifiable assets by industry segment
Total revenues	(12,941)	(7,654)	(33,641)	(21,779)
Operating income (loss)	(677)	$ 564	(1,556)	$ 979
Segments assets	$ (4,246)		$ (4,246)		$ (2,690)

Number of customers that accounted for significant risk.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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.

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