Note 13 - Employee Benefit Plan	12 Months Ended
Dec. 31, 2019
Notes to Financial Statements
Compensation and Employee Benefit Plans [Text Block]	13. Employee Benefit Plan The Company has established a 401(k) tax-deferred savings plan (the “Plan”) which permits participants to make contributions by salary deduction pursuant to Section 401(k) of the Code. The Company may, at its discretion, make matching contributions to the Plan. Furthermore, the Company is responsible for administrative costs of the Plan. The Company accrued $1,976, $1,800 and $1,137 in contributions to the Plan for the years ended December 31, 2019, 2018 and 2017, 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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