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PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
PROPERTY AND EQUIPMENT (Details) - USD ($) $ in Thousands	Jan. 31, 2018	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Property and equipment
Property and equipment, gross		$ 265,086	$ 246,836
Less accumulated depreciation and amortization		(137,701)	(131,312)
Property and equipment, net		127,385	115,524
Depreciation expense		20,500	43,300	$ 56,000
Mexican government
Contract with Mexican government
Term of agreement with Mexican government to provide security screening services	2 years
Net book value of certain fixed assets transferred	$ 29,500
Recognized amortization expense		14,300	6,900
Mexican government \| Prepaid expenses and other current assets
Contract with Mexican government
Remaining cost to obtain the contract		7,700
Land
Property and equipment
Property and equipment, gross		16,564	16,569
Buildings, civil works and improvements
Property and equipment
Property and equipment, gross		$ 55,391	56,585
Buildings, civil works and improvements \| Minimum
Property and equipment
Estimated Useful Lives		5 years
Buildings, civil works and improvements \| Maximum
Property and equipment
Estimated Useful Lives		40 years
Leasehold improvements
Property and equipment
Property and equipment, gross		$ 8,311	9,681
Leasehold improvements \| Minimum
Property and equipment
Estimated Useful Lives		1 year
Leasehold improvements \| Maximum
Property and equipment
Estimated Useful Lives		13 years
Equipment and tooling
Property and equipment
Property and equipment, gross		$ 128,428	117,294
Equipment and tooling \| Minimum
Property and equipment
Estimated Useful Lives		3 years
Equipment and tooling \| Maximum
Property and equipment
Estimated Useful Lives		10 years
Furniture and fixtures
Property and equipment
Property and equipment, gross		$ 3,190	3,331
Furniture and fixtures \| Minimum
Property and equipment
Estimated Useful Lives		3 years
Furniture and fixtures \| Maximum
Property and equipment
Estimated Useful Lives		10 years
Computer equipment
Property and equipment
Property and equipment, gross		$ 18,733	18,759
Computer equipment \| Minimum
Property and equipment
Estimated Useful Lives		3 years
Computer equipment \| Maximum
Property and equipment
Estimated Useful Lives		5 years
Computer software
Property and equipment
Property and equipment, gross		$ 20,146	19,509
Computer software \| Minimum
Property and equipment
Estimated Useful Lives		3 years
Computer software \| Maximum
Property and equipment
Estimated Useful Lives		10 years
Computer software implementation in process
Property and equipment
Property and equipment, gross		$ 8,563	4,318
Construction in process
Property and equipment
Property and equipment, gross		$ 5,760	$ 790