Operating Segment, Geographic Information and Significant Customers - Net Revenue by End Market (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	$ 152,867	$ 116,336	$ 117,912	$ 106,069	$ 115,608	$ 107,317	$ 98,014	$ 87,649	$ 493,184	$ 408,588	$ 270,154
Domestic
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									410,050	341,699	220,253
International/Foreign Military Sales
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues									$ 83,134	$ 66,889	$ 49,901