Segment Information - Operations and Identifiable Assets (Details) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2017 USD ($) customer	Dec. 31, 2016 USD ($) customer	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Jun. 30, 2017 USD ($)
Operations and identifiable assets by industry segment
Number of identifiable industry segments \| segment			3
Total revenues	$ 277,528	$ 242,548	$ 534,661	$ 463,403
Operating income (loss)	18,147	$ 8,693	37,541	$ 10,792
Segments assets	$ 1,346,759		$ 1,346,759		$ 1,230,087
SAT in Mexico \| Revenue \| Customer
Operations and identifiable assets by industry segment
Number of major customers \| customer	1	1
Percentage of benchmark derived from specified source	12.00%	12.00%	12.00%	13.00%
Operating Segments \| Security Division
Operations and identifiable assets by industry segment
Total revenues	$ 172,269	$ 139,504	$ 334,514	$ 263,213
Operating income (loss)	22,471	9,130	45,164	18,480
Segments assets	917,953		917,953		785,230
Operating Segments \| Healthcare Division
Operations and identifiable assets by industry segment
Total revenues	52,506	51,110	98,035	96,760
Operating income (loss)	603	801	1,450	(2,463)
Segments assets	170,495		170,495		186,021
Operating Segments \| Optoelectronics and Manufacturing division
Operations and identifiable assets by industry segment
Total revenues	63,886	60,602	122,812	117,556
Operating income (loss)	4,502	5,525	9,677	10,175
Segments assets	196,208		196,208		196,567
Corporate
Operations and identifiable assets by industry segment
Operating income (loss)	(9,118)	(6,802)	(17,871)	(15,815)
Segments assets	65,672		65,672		64,959
Eliminations
Operations and identifiable assets by industry segment
Total revenues	(11,133)	(8,668)	(20,700)	(14,126)
Operating income (loss)	(311)	$ 39	(879)	$ 415
Segments assets	$ (3,569)		$ (3,569)		$ (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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