Basis of Presentation - Fair Value (Details) $ in Thousands	6 Months Ended
Dec. 31, 2016 USD ($) item	Jun. 30, 2016 USD ($)
Fair value of financial instruments
Liabilities - Contingent payment obligations	$ 16,798	$ 17,117
Property and Equipment
Net value of turnkey security screening program assets at Mexico	$ 15,000
Goodwill Impairment
Total number of reporting units \| item	3
Number of reporting units that are not tested with two-step goodwill impairment \| item	2
Goodwill impairment without two-step impairment test	$ 0
Percentage of decrease hypothetically applied to the fair value	10.00%
Goodwill impairment after two-step goodwill impairment test	$ 0
Recurring
Fair value of financial instruments
Equity securities	330	354
Insurance company contracts	24,273	21,353
Interest rate contract	16	(31)
Total assets	24,619	21,676
Liabilities - Contingent payment obligations	16,798	17,117
Recurring \| Level 1
Fair value of financial instruments
Equity securities	330	354
Total assets	330	354
Recurring \| Level 2
Fair value of financial instruments
Insurance company contracts	24,273	21,353
Interest rate contract	16	(31)
Total assets	24,289	21,322
Recurring \| Level 3
Fair value of financial instruments
Total assets	0	0
Liabilities - Contingent payment obligations	$ 16,798	$ 17,117

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Number of reporting units that are not tested for two-step impairment of goodwill.

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Percentage of carrying amount of reporting unit in excess of fair value.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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Fair value of investments in trading equity securities and other forms of trading securities that provide ownership interests.

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