Operating Segment - Product Category (Details) - USD ($)	3 Months Ended
Jun. 25, 2017	Jun. 26, 2016
Revenue and Gross Profit from External Customers
Revenues	$ 140,010,800	$ 128,860,000
Gross Profit	29,166,800	27,106,000
Base station infrastructure
Revenue and Gross Profit from External Customers
Revenues	59,070,000	52,395,000
Gross Profit	14,057,000	13,428,000
Network systems
Revenue and Gross Profit from External Customers
Revenues	23,837,000	18,430,000
Gross Profit	3,829,000	2,898,000
Installation, test and maintenance
Revenue and Gross Profit from External Customers
Revenues	6,993,000	8,755,000
Gross Profit	1,419,000	1,568,000
Mobile device accessories
Revenue and Gross Profit from External Customers
Revenues	50,111,000	49,280,000
Gross Profit	$ 9,862,000	$ 9,212,000

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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