Receivables - Schedule of Receivables (Details) - USD ($) $ in Thousands |
Mar. 29, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Receivables [Abstract] | ||
| Billed receivables | $ 42,147 | $ 44,868 |
| Unbilled receivables (contract assets) | 195,696 | 181,009 |
| Other | 6,273 | 6,242 |
| Total receivables | 244,116 | $ 232,119 |
| Estimate of unbilled contract receivables | $ 2,300 |