Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Dec. 30, 2017
Disclosure Accrued Expenses [Abstract]
Accrued payroll and related expenses	$ 62,737		$ 67,935
Standard Product Warranty Accrual, Current	54,069		52,834
Accrued warranty	54,069		52,834
Contract with Customer, Liability	51,276	$ 47,647	31,069
Product Liability Contingency, Loss Exposure in Excess of Accrual, High Estimate	5,749		6,068
Accured Restructuring Liabilities, Current	1,561		1,715
Accrued customer rebates	25,917		48,590
Accrued Product Liability And Workers Compensation Liability Current	10,872		11,976
Accrued agent commission	11,443		11,035
Accrued professional services	17,515		18,250
Sales and Excise Tax Payable, Current	14,481		20,881
Other accrued expenses	49,512		51,818
Accrued expenses	$ 305,132		$ 322,171