Note 11 - Profit-sharing Plan	12 Months Ended
Dec. 31, 2021
Notes to Financial Statements
Compensation and Employee Benefit Plans [Text Block]	11. Profit-Sharing Plan We offer a 401(k) profit-sharing plan (the Plan) covering eligible U.S. employees to make tax-deferred contributions, a portion of which are matched by us. We may also make discretionary profit sharing contributions to the Plan in an amount determined by our Board of Directors. Our contributions vest ratably over six years of employment and amounted to approximately $0.5 million, $0.3 million and $0.4 million for 2021, 2020 and 2019, respectively. A similar plan is offered to our Canadian employees.

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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