Note 4 - Accrued Liabilities (Detail) - Warranty Reserve Roll-Forward (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Balance at beginning of year	$ 561	$ 764
Warranty costs	(124)	(333)
Unused warranty provision	(213)	(220)
Warranty provision for product sales	219	515
Balance at end of period	$ 443	$ 726

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.

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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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The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

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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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