Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2013	Dec. 31, 2012
Schedule of Inventory [Line Items]
Raw materials	$ 27,217	$ 28,146
Finished goods	8,614	6,188
Sales demonstration inventory	18,460	18,729
Reserve for excess and obsolete	(4,267)	(4,169)
Inventory	50,024	48,894
Service inventory	$ 18,316	$ 19,125

The amount of the valuation account as of the balance sheet date which reduces the carrying amount of inventory to net realizable value; takes into consideration such factors as market value, excessive quantities based on expected sales, technological obsolescence, and shrinkage. May also provide for estimated product returns or price concessions pertaining to product cost.

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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+ Details