Employment Benefits	12 Months Ended
Employment Benefits	Dec. 31, 2020
Employment Benefits [Abstract]
Employment Benefits	10. Employment Benefits We have employee 401(k) salary deferral plans covering all employees. Employees could make contributions by withholding a percentage of their salary up to the IRS annual limits of $19,500 and $26,000 in 2020 for employees under 50 years old and employees 50 years old or over, respectively. We made approximately $5.7 million, $6.4 million and $5.7 million in matching contributions for the years ended December 31, 2020, 2019 and 2018, respectively.

The entire disclosure for retirement benefits.

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