Segment Information - Operations and Identifiable Assets (Details) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2016 USD ($) customer	Dec. 31, 2015 USD ($) customer	Dec. 31, 2016 USD ($) item	Dec. 31, 2015 USD ($)	Jun. 30, 2016 USD ($)
Operations and identifiable assets by industry segment
Number of identifiable industry segments \| item			3
Total revenues	$ 242,548	$ 197,339	$ 463,403	$ 397,389
Income (loss) from operations	8,693	$ 781	10,792	$ 16,478
Segments assets	$ 1,258,005		$ 1,258,005		$ 991,723
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%	14.00%	13.00%	15.00%
Operating Segments \| Security Division
Operations and identifiable assets by industry segment
Total revenues	$ 139,504	$ 93,720	$ 263,213	$ 190,130
Income (loss) from operations	9,130	2,534	18,480	15,169
Segments assets	836,182		836,182		519,068
Operating Segments \| Healthcare Division
Operations and identifiable assets by industry segment
Total revenues	51,110	55,548	96,760	107,013
Income (loss) from operations	801	3,380	(2,463)	6,318
Segments assets	192,909		192,909		200,067
Operating Segments \| Optoelectronics and Manufacturing Division
Operations and identifiable assets by industry segment
Total revenues	60,602	60,560	117,556	123,108
Income (loss) from operations	5,525	3,192	10,175	8,753
Segments assets	196,311		196,311		211,337
Corporate
Operations and identifiable assets by industry segment
Income (loss) from operations	(6,802)	(7,903)	(15,815)	(13,105)
Segments assets	35,907		35,907		64,970
Eliminations
Operations and identifiable assets by industry segment
Total revenues	(8,668)	(12,489)	(14,126)	(22,862)
Income (loss) from operations	39	$ (422)	415	$ (657)
Segments assets	$ (3,304)		$ (3,304)		$ (3,719)

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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