CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash Flows from Operating Activities:
Net income	$ 506,882	$ 582,073
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	83,180	76,901
Impairment charges	2,346	5,148
Provision for credit losses	5,112	1,719
Deferred income taxes	(36,890)	4,049
Share-based compensation expense	36,491	28,042
Other	2,032	2,402
Changes in assets and liabilities:
Accounts receivable	(35,061)	(49,050)
Inventories	(99,621)	(46,891)
Other assets and liabilities	(87,566)	(51,961)
Accounts payable	(3,930)	637
Deferred revenue	(3,419)	(7,487)
Net cash provided by operating activities	369,556	545,582
Cash Flows from Investing Activities:
Purchases of property and equipment	(99,609)	(87,761)
Acquisition of intangible assets	(10,000)	0
Equity investment	(25,000)	0
Acquisitions of a business, net of cash acquired	(11,512)	(161,166)
Net cash used by investing activities	(146,121)	(248,927)
Cash Flows from Financing Activities:
Borrowings under revolving credit facility, net	559,500	0
Payment of senior debt	(75,000)	(50,000)
Payments of acquisition-related contingent consideration and holdbacks	(5,730)	(1,500)
Repurchases of common stock, net	(745,691)	(502,021)
Proceeds from exercises of stock options and employee stock purchase plans	23,257	37,428
Shares withheld for statutory tax withholding payments on restricted stock	(10,552)	(15,501)
Net cash used by financing activities	(254,216)	(531,594)
Net effect of changes in exchange rates on cash	(14,497)	(3,786)
Net decrease in cash and cash equivalents	(45,278)	(238,725)
Cash and cash equivalents at beginning of period	144,454	383,928
Cash and cash equivalents at end of period	99,176	145,203
Supplemental Cash Flow Information:
Cash paid for income taxes	179,720	96,103
Unpaid property and equipment, reflected in accounts payable and accrued liabilities	$ 19,661	$ 14,734