CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019
OPERATING ACTIVITIES
Net income	$ 71,009	$ 116,428
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	41,953	38,988
Amortization of intangibles	29,912	30,068
Deferred revenue	(438)	(228)
Impairment charges	36,078	322
Stock-based compensation	14,544	15,738
(Gain) loss on investments and other assets	(1,200)	559
Deferred income taxes	1,567	(203)
Other	(8,549)	8,267
Changes in operating assets and liabilities:
Trade receivables	(29,362)	2,781
Inventories	(1,611)	18,102
Accounts payable	6,661	(29,453)
Accrued liabilities and income taxes	(2,095)	(44,241)
Prepaid expenses and other assets	5,787	3,735
Net cash provided by operating activities	164,256	160,863
INVESTING ACTIVITIES
Acquisitions of businesses, net of cash acquired	0	(775)
Purchases of property, plant, and equipment	(41,536)	(38,397)
Net proceeds from sale of property, plant and equipment	148	6,212
Net cash used in investing activities	(41,388)	(32,960)
FINANCING ACTIVITIES
Proceeds of revolving credit facility	240,000	0
Payments of revolving credit facility	(60,000)	0
Payments of term loan	(145,000)	(7,500)
Net proceeds related to stock-based award activities	6,437	4,412
Purchases of common stock	(22,927)	(99,387)
Debt issuance costs	(1,786)	0
Cash dividends paid	(35,100)	(32,990)
Net cash used in financing activities	(18,376)	(135,465)
Effect of exchange rate changes on cash and cash equivalents	6,259	(6,114)
Increase (decrease) in cash and cash equivalents	110,751	(13,676)
Cash and cash equivalents at beginning of period	531,139	489,733
Cash and cash equivalents at end of period	641,890	476,057
Supplementary Cash Flow Information
Cash paid during the period for interest	17,228	17,872
Capital expenditures, not yet paid	$ 6,267	$ 8,978