Note 4 - Balance Sheet Components (Details) - Accrued Liabilities - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Accrued Liabilities [Abstract]
Dividends and dividend equivalents	$ 8,389	$ 6,080
Deferred revenue and customer prepayments	3,849	3,908
Stock rotation reserve	1,691	1,757
Other	4,473	2,958
Total	$ 18,402	$ 14,703

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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