Note 4 - Accrued Liabilities (Detail) - Warranty Reserve Roll-Forward (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Balance at beginning of year	$ 331	$ 561
Warranty provision for product sales	103	101
Settlements made during the period	(93)	(6)
Unused warranty provision	(66)	(83)
Balance at end of period	$ 275	$ 573

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

-Publisher FASB

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-SubTopic 10

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-Paragraph 8

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Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

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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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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