Consolidated Statements Of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities:
Net income	$ 254,860,000	$ 240,755,000	$ 85,066,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	74,975,000	65,116,000	58,208,000
Amortization	66,428,000	62,152,000	44,023,000
Share-based compensation expense	19,629,000	17,112,000	15,306,000
Provision for deferred income taxes	(14,008,000)	(11,876,000)	1,628,000
Charge for excess and obsolete inventory	11,433,000	4,496,000	9,405,000
Amortization of debt issuance costs	2,330,000	1,834,000	2,864,000
Loss on extinguishment of debt	0	2,429,000	20,687,000
Other	9,788,000	9,948,000	16,026,000
Changes in operating assets and liabilities, net of effects of acquisitions:
Trade accounts receivable and notes receivable	(3,164,000)	(17,473,000)	(15,401,000)
Inventories	(21,354,000)	(38,100,000)	(20,214,000)
Accounts payable and other accrued liabilities	(22,647,000)	19,950,000	15,975,000
Other current assets	7,784,000	(13,677,000)	(3,330,000)
Income taxes payable, refundable income taxes and noncurrent taxes payable	(3,494,000)	(30,381,000)	64,516,000
Other	(262,000)	291,000	(1,386,000)
Net cash provided by operating activities	382,298,000	312,576,000	293,373,000
Investing activities:
Acquisition of property and equipment	(112,355,000)	(110,153,000)	(93,597,000)
Acquisition of business, net of cash acquired	(277,369,000)	(380,694,000)	(20,000,000)
Other	3,884,000	4,903,000	1,142,000
Net cash used in investing activities	(385,840,000)	(485,944,000)	(112,455,000)
Financing activities:
Proceeds from long-term debt	0	402,000,000	550,000,000
Payments of long-term debt	(4,000,000)	(135,850,000)	(460,000,000)
Payments for debt issuance costs	0	(7,400,000)	(7,333,000)
Payments for debt extinguishment costs	0	0	(16,200,000)
Payments for dividends	(40,566,000)	(39,591,000)	(9,896,000)
Issuance of common stock from employee stock plans	7,291,000	5,577,000	5,566,000
Taxes paid related to net share settlement of equity awards	(8,722,000)	(14,686,000)	(5,887,000)
Repurchase and retirement of common stock	(80,321,000)	(173,781,000)	(28,000,000)
Other	(502,000)	(1,858,000)	(999,000)
Net cash (used in) provided by financing activities	(126,820,000)	34,411,000	27,251,000
Effect of exchange rate changes on cash and cash equivalents	211,000	(4,389,000)	10,850,000
(Decrease) increase in cash and cash equivalents	(130,151,000)	(143,346,000)	219,019,000
Cash and cash equivalents at beginning of year	482,062,000	625,408,000	406,389,000
Cash and cash equivalents at end of year	351,911,000	482,062,000	625,408,000
Supplemental Cash Flow Information
Contingent consideration obligation	686,000	0	0
Deferred acquisition payments, net	19,848,000	0	0
Equipment purchases in accounts payable	11,285,000	17,624,000	8,608,000
Repurchase and retirement of common stock to be settled	0	5,534,000	0
Capital lease obligations incurred	0	0	4,768,000
Dividends Payable	349,000	131,000	0
Schedule of interest and income taxes paid:
Interest paid	41,711,000	26,248,000	30,392,000
Income taxes, net of refunds received	$ 77,970,000	$ 54,415,000	$ 33,330,000