Operating Segment, Geographic Information and Significant Customers - Net Revenue by End Application (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, 2019	Jun. 30, 2018	Jun. 30, 2017
Revenue from External Customer [Line Items]
Net revenues	$ 176,963	$ 174,636	$ 159,089	$ 144,056	$ 152,867	$ 116,336	$ 117,912	$ 106,069	$ 654,744	$ 493,184	$ 408,588
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)									259	(596)
Radar End User Applications
Revenue from External Customer [Line Items]
Net revenues									164,046	159,737	150,441
Electronic Warfare End User Applications
Revenue from External Customer [Line Items]
Net revenues									128,841	114,801	106,446
Other Sensor And Effector Applications [Member]
Revenue from External Customer [Line Items]
Net revenues									90,245	48,088	27,719
Total Sensor And Effector Applications [Member]
Revenue from External Customer [Line Items]
Net revenues									383,132	322,626	284,606
C4I Applications [Member]
Revenue from External Customer [Line Items]
Net revenues									183,172	87,414	31,679
Other End User Applications
Revenue from External Customer [Line Items]
Net revenues									$ 88,440	$ 83,144	$ 92,303