Composition of Certain Financial Statement Captions - Schedule of Other Accrued Liabilities (Details) - USD ($)
$ in Thousands
Mar. 30, 2018
Dec. 31, 2017
Other Accrued Liabilities    
Workers' compensation, auto and general liability reserve $ 4,486 $ 4,615
Contract related reserves 10,233 7,426
Other accrued liabilities 13,854 7,168
Total $ 28,573 $ 19,209