Employee Benefit Plans	12 Months Ended
Dec. 31, 2020
Employee Benefit Plans [Abstract]
Employee Benefit Plans	16. EMPLOYEE BENEFIT PLANS The Company sponsors the AtriCure, Inc. 401(k) Plan (401(k) Plan), a defined contribution plan covering substantially all U.S. employees of the Company. Eligible employees may contribute pre-tax annual compensation up to specified maximums under the Internal Revenue Code. During 2020, 2019 and 2018, the Company made matching contributions of 50% on the first 6% of employee contributions to the 401(k) Plan. The Company’s matching contributions expensed during 2020, 2019 and 2018 were $2,237, $1,915 and $1,560. Additional amounts may be contributed to the 401(k) Plan at the discretion of the Company’s Board of Directors, however, no such discretionary contributions were made during 2020, 2019 or 2018. The Company also provides retirement benefits for employees of AtriCure Europe B.V. and other foreign subsidiaries. Total contributions to retirement plans for these employees were $244, $248 and $243 in 2020, 2019 and 2018.

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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