Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 29, 2019	Dec. 31, 2018	Mar. 30, 2018	Dec. 31, 2017
Other Liabilities Disclosure [Abstract]
Accrued compensation and benefits	$ 16,503	$ 24,545
Accrued warranty	4,884	4,510	$ 5,054	$ 4,835
Contract liabilities, current portion	3,338	4,165
Other	16,449	13,075
Total	$ 41,174	$ 46,295

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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