Composition of Certain Financial Statement Captions - Schedule of Other Accrued Liabilities (Details) - USD ($) $ in Thousands |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|
| Other Accrued Liabilities | ||
| Workers' compensation, auto and general liability reserve | $ 4,042 | $ 4,264 |
| Current operating lease liabilities | 6,245 | 5,743 |
| Contract related reserves | 13,064 | 14,057 |
| Other | 17,306 | 13,345 |
| Total | $ 40,657 | $ 37,409 |