Note 4 - Accrued Liabilities (Detail) - Warranty Reserve Roll-Forward (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Balance at beginning of year	$ 561	$ 764
Warranty provision for product sales	802	747
Settlements made during the period	(154)	(607)
Unused warranty provision	(350)	(324)
Balance at end of period	$ 859	$ 580

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard and extended product warranties (including adjustments for changes in estimates).

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Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

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