Note 15 - Employee Benefit Plan	12 Months Ended
Dec. 31, 2020
Notes to Financial Statements
Compensation and Employee Benefit Plans [Text Block]	15. Employee Benefit Plan The Company’s U.S. employees are eligible to participate in the Company’s 401(k) savings plan. Employees may elect to contribute a percentage of their compensation to the plan, and the Company will make 140% matching contributions up to a limit of 5% of an employee’s eligible compensation. In addition, the Company may make annual discretionary contributions. The Company made matching contributions of $1.7 million, $0.8 million, and $0.8 million for the years ended December 31, 2020, 2019, and 2018, respectively.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

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