CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
Mar. 30, 2019	Mar. 31, 2018
Operating Activities
Net income	$ 13,033	$ 14,264
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	7,486	8,172
Slow moving inventory valuation adjustment	409	360
Stock-based compensation	1,541	1,144
Deferred income taxes	411	(744)
Changes in operating assets and liabilities:
Trade receivables	(7,187)	(1,047)
Inventories	(5,471)	13,242
Trade accounts payable and accrued expenses	(4,485)	(3,974)
Contract liability to customers	(3,518)	7,081
Employee compensation and benefits	(8,157)	1,361
Product liability	501	(70)
Prepaid expenses, other assets and other liabilities	(4,872)	898
Income taxes payable	7	4,625
Cash (used for) provided by operating activities	(10,302)	45,312
Investing Activities
Property, plant and equipment additions	(2,711)	(1,402)
Purchases of short-term investments	(44,961)
Proceeds from maturities of short-term investments	59,763
Cash provided by (used for) investing activities	12,091	(1,402)
Financing Activities
Remittance of taxes withheld from employees related to share-based compensation		(718)
Dividends paid	(4,887)	(4,012)
Cash used for financing activities	(4,887)	(4,730)
(Decrease) increase in cash and cash equivalents	(3,098)	39,180
Cash and cash equivalents at beginning of period	38,492	63,487
Cash and cash equivalents at end of period	$ 35,394	$ 102,667

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