Note 4 - Balance Sheet Components - Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
RSU tax withholding proceeds receivable	$ 5,744	$ 6,106
Prepaid expense	18,444	7,991
Accrued interest receivable	2,530	2,490
Assets for product returns	1,824	1,585
Other	1,137	1,433
Total	$ 29,679	$ 19,605

Product return assets that are expected to be received within one year or the normal operating cycle, if longer.

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Amount of proceeds receivable related to tax withholding for Share-based payment arrangement.

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Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Amount of current assets classified as other.

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Amount of other miscellaneous assets expected to be realized or consumed within one year or operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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