Business Segments - Market Unit Activity (Details)	3 Months Ended
Jun. 26, 2016 USD ($) segment product	Jun. 28, 2015 USD ($)
Operating Segment
Number of reportable segment \| segment	1
Number of product categories \| product	4
Market unit activity
Revenues	$ 128,860,000	$ 134,664,000
Gross Profit	27,106,000	28,981,900
Public Carriers, Contractors & Program Managers
Market unit activity
Revenues	16,578,000	25,151,000
Gross Profit	3,017,000	4,414,000
Government System Operators
Market unit activity
Revenues	9,852,000	7,883,000
Gross Profit	2,140,000	1,947,000
Private System Operators
Market unit activity
Revenues	21,515,000	22,022,000
Gross Profit	4,964,000	5,659,000
Commercial Dealers & Resellers
Market unit activity
Revenues	33,430,000	33,488,000
Gross Profit	8,983,000	8,771,000
Retailer, Independent Dealer Agents & Carriers
Market unit activity
Revenues	47,485,000	46,120,000
Gross Profit	$ 8,002,000	$ 8,191,000

Number of product categories of entity.

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- Definition

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)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

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.

+ References

No definition available.

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- References

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- Details

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