Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 28, 2018	Dec. 31, 2017	Sep. 29, 2017	Dec. 31, 2016
Other Liabilities Disclosure [Abstract]
Accrued compensation and benefits	$ 23,926	$ 17,348
Accrued warranty	5,041	4,835	$ 4,773	$ 3,142
Customer deposits	3,392	3,634
Other	16,306	17,497
Total	$ 48,665	$ 43,314

The current portion of money or property received from customers which is either to be returned upon satisfactory contract completion or applied to customer receivables in accordance with the terms of the contract or the understandings.

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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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