Business Acquisitions, Goodwill and Other Intangible Assets - Identifiable Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Jun. 30, 2016
Finite-lived Intangible Assets
Finite-Lived Intangible Assets, Gross	$ 61,118	$ 61,118
Accumulated Amortization of Identifiable Intangible Assets	(18,291)	(15,575)
Finite-Lived Intangible Assets, Net	42,827	45,543
Indefinite-lived Intangible Assets
Indefinite-Lived Intangible Assets (Excluding Goodwill)	61,544	61,544
Intangible Assets Net Excluding Goodwill Accumulated Amortization	(18,291)	(15,575)
Intangible Assets, Net (Excluding Goodwill)	43,253	45,969
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2017	7,443
2018	9,183
2019	8,367
2020	7,821
2021	7,274
2022 and thereafter	2,739
Engineering licenses
Indefinite-lived Intangible Assets
Indefinite-Lived Intangible Assets (Excluding Goodwill)	426	426
Customer relationships
Finite-lived Intangible Assets
Finite-Lived Intangible Assets, Gross	59,218	59,218
Accumulated Amortization of Identifiable Intangible Assets	(17,374)	(14,933)
Finite-Lived Intangible Assets, Net	41,844	44,285
Contract backlog
Finite-lived Intangible Assets
Finite-Lived Intangible Assets, Gross	900	900
Accumulated Amortization of Identifiable Intangible Assets	(750)	(525)
Finite-Lived Intangible Assets, Net	150	375
Technology
Finite-lived Intangible Assets
Finite-Lived Intangible Assets, Gross	1,000	1,000
Accumulated Amortization of Identifiable Intangible Assets	(167)	(117)
Finite-Lived Intangible Assets, Net	$ 833	$ 883