Company Retirement Plans (Details) - United States - 401(k) Plan - USD ($) $ in Thousands |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
Company retirement plans | |||
Employer discretionary contributions | $ 0 | $ 0 | $ 0 |
Employer's contribution | $ 7,000 | $ 4,600 | $ 4,200 |