Operating Segment, Geographic Information and Significant Customers - Programs Comprising Ten Percent or More of Revenues (Detail) - Revenues	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Concentration risk, percent	0.00%	22.00%	46.00%
SEWIP | Program Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percent		12.00%
Aegis | Program Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percent		10.00%	12.00%
Patriot | Program Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percent			18.00%
F-35 | Program Concentration Risk
Segment Reporting Information [Line Items]
Concentration risk, percent			16.00%