Business Segments - Segment Activity (Details)	3 Months Ended
Jun. 28, 2020 USD ($) segment product	Jun. 30, 2019 USD ($)
Business Segments
Number of reportable segment \| segment	2
Number of product categories \| product	4
Market unit activity
Revenues	$ 119,813,500	$ 130,729,300
Gross Profit	18,825,700	25,263,500
Loss before benefit from income taxes	(5,019,400)	(3,529,700)
Segments
Market unit activity
Directly allocable expenses	9,294,000	12,585,000
Loss before benefit from income taxes	9,532,000	12,679,000
Corporate
Market unit activity
Directly allocable expenses	14,551,000	16,209,000
Public carrier
Market unit activity
Revenues	39,255,000	33,486,000
Gross Profit	3,728,000	4,253,000
Value-added resellers and integrators
Market unit activity
Revenues	57,223,000	65,194,000
Gross Profit	12,725,000	15,969,000
Retail
Market unit activity
Revenues	23,336,000	32,049,000
Gross Profit	2,373,000	5,042,000
Commercial Segment
Market unit activity
Revenues	96,478,000	98,680,000
Gross Profit	16,453,000	20,222,000
Commercial Segment \| Segments
Market unit activity
Directly allocable expenses	7,462,000	9,570,000
Loss before benefit from income taxes	8,991,000	10,652,000
Commercial Segment \| Public carrier
Market unit activity
Revenues	39,255,000	33,486,000
Gross Profit	3,728,000	4,253,000
Commercial Segment \| Value-added resellers and integrators
Market unit activity
Revenues	57,223,000	65,194,000
Gross Profit	12,725,000	15,969,000
Retail Segment
Market unit activity
Revenues	23,336,000	32,049,000
Gross Profit	2,373,000	5,042,000
Retail Segment \| Segments
Market unit activity
Directly allocable expenses	1,832,000	3,015,000
Loss before benefit from income taxes	541,000	2,027,000
Retail Segment \| Retail
Market unit activity
Revenues	23,336,000	32,049,000
Gross Profit	$ 2,373,000	$ 5,042,000

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Also includes the net amount of nonoperating interest (income) expense.

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

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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