CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities:
Net income	$ 542,372	$ 448,752	$ 715,501
Adjustments to reconcile net income from operations to net cash provided by operating activities:
Depreciation	100,977	92,118	90,763
Stock-based compensation	60,122	57,682	48,228
Provision for excess and obsolete inventory	18,922	28,358	31,452
Amortization	18,764	18,768	19,912
Losses (gains) on investments	10,056	(14,915)	9,985
Equity in net earnings of affiliate	7,211	0	0
Gain on sale of business	(57,119)	0	0
Deferred taxes	(46,360)	(37,642)	(38,693)
Retirement plans actuarial (gains) losses	(4,355)	2,703	(25,584)
Loss (gain) on sale of asset	0	0	(3,410)
Other	(2,290)	(955)	2,353
Changes in operating assets and liabilities, net of businesses acquired:
Accounts receivable	(52,659)	70,977	50,628
Inventories	8,707	5,327	(80,809)
Prepayments and other assets	119,454	(43,101)	(140,713)
Accounts payable and other accrued expenses	(54,386)	46,782	(60,507)
Deferred revenue and customer advances	12,176	(57,210)	(6,233)
Retirement plan contributions	(5,814)	(5,492)	(5,116)
Income taxes	(3,602)	(26,921)	(29,834)
Net cash provided by operating activities	672,176	585,231	577,923
Cash flows from investing activities:
Investments in businesses	(532,060)	0	0
Purchases of property, plant and equipment	(198,095)	(159,642)	(163,249)
Purchases of marketable securities	(45,796)	(161,906)	(287,409)
Issuance of convertible loan	0	(5,000)	0
Proceeds from the sale of a business, net of cash and cash equivalents sold	90,348	0	0
Proceeds from maturities of marketable securities	38,353	85,042	222,941
Proceeds from sales of marketable securities	24,035	61,401	268,058
Proceeds from life insurance	873	460	0
Proceeds from sale of asset	0	0	3,410
Net cash (used for) provided by investing activities	(622,342)	(179,645)	43,751
Cash flows from financing activities:
Repurchase of common stock	(198,574)	(397,241)	(752,082)
Payments of borrowings on revolving credit facility	(185,000)	0	0
Dividend payments	(76,423)	(67,878)	(69,711)
Payments related to net settlement of employee stock compensation awards	(14,100)	(20,788)	(33,170)
Payments of convertible debt principal	0	(50,264)	(66,759)
Proceeds from borrowings on revolving credit facility	185,000	0	0
Issuance of common stock under stock purchase and stock option plans	37,330	34,259	28,733
Net cash used for financing activities	(251,767)	(501,912)	(892,989)
Effects of exchange rate changes on cash and cash equivalents	(2,284)	(876)	3,889
(Decrease) Increase in cash and cash equivalents	(204,217)	(97,202)	(267,426)
Cash and cash equivalents at beginning of year	757,571	854,773	1,122,199
Cash and cash equivalents at end of year	553,354	757,571	854,773
Cash paid for:
Interest	767	296	1,498
Income taxes	121,428	140,239	193,246
Non-cash investing activities:
Capital expenditures incurred but not yet paid:	$ 3,893	$ 2,735	$ 1,826