Note 6 - Note Payable - Summary of Note Payable (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
2017	$ 2,719
2018	4,463
2019	4,512
Total payments	11,694
Less: Amount representing interest	(1,694)
Present value of obligations	10,000
Less: Unamortized debt discount	(371)
	9,629
Less: Note payable, noncurrent portion	7,762	$ 0
Note payable, current portion	$ 1,867	$ 4,446

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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