Business Segments - Product Category (Details) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 27, 2015	Dec. 28, 2014	Dec. 27, 2015	Dec. 28, 2014
Revenue and Gross Profit from External Customers
Revenue from external customers	$ 139,510,700	$ 135,188,700	$ 416,528,000	$ 436,656,800
Gross profit	29,453,400	28,820,900	88,947,000	93,326,700
Base Station Infrastructure
Revenue and Gross Profit from External Customers
Revenue from external customers	51,571,000	50,631,000	161,669,000	177,647,000
Gross profit	13,381,000	13,018,000	41,139,000	44,415,000
Network Systems
Revenue and Gross Profit from External Customers
Revenue from external customers	22,922,000	20,299,000	66,541,000	78,339,000
Gross profit	3,717,000	3,361,000	10,200,000	10,904,000
Installation, Test and Maintenance
Revenue and Gross Profit from External Customers
Revenue from external customers	9,851,000	11,938,000	27,481,000	33,523,000
Gross profit	1,687,000	2,314,000	5,184,000	6,682,000
Mobile Device Accessories
Revenue and Gross Profit from External Customers
Revenue from external customers	55,167,000	52,321,000	160,837,000	147,148,000
Gross profit	$ 10,668,000	$ 10,128,000	$ 32,424,000	$ 31,326,000