Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Cash flows from operating activities:
Net income	$ 109,802	$ 79,566
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	9,987	9,120
Amortization of premium on available-for-sale securities	260	1,348
(Gain) loss on deferred compensation plan investments	(2,534)	2,192
Deferred taxes, net	(622)	(381)
Stock-based compensation expense	37,009	39,811
Changes in operating assets and liabilities:
Accounts receivable	(1,558)	(15,506)
Inventories	16,063	(51,797)
Other assets	213	(5,916)
Accounts payable	(880)	(4,177)
Accrued compensation and related benefits	13,422	27,382
Income tax liabilities	20,137	16,017
Other accrued liabilities	17,508	9,760
Net cash provided by operating activities	218,807	107,419
Cash flows from investing activities:
Purchases of property and equipment	(8,854)	(26,877)
Purchases of investments	(129,321)	(16,243)
Maturities and sales of investments	152,698	32,267
Contributions to deferred compensation plan, net	(2,209)	(760)
Net cash provided by (used in) investing activities	12,314	(11,613)
Cash flows from financing activities:
Property and equipment purchased on extended payment terms	(374)	(528)
Proceeds from common stock issued under the employee equity incentive plan	1,110	2,318
Proceeds from common stock issued under the employee stock purchase plan	3,737	2,786
Dividends and dividend equivalents paid	(36,725)	(28,825)
Net cash used in financing activities	(32,252)	(24,249)
Effect of change in exchange rates	1,497	(220)
Net increase in cash, cash equivalents and restricted cash	200,366	71,337
Cash, cash equivalents and restricted cash, beginning of period	288,729	189,389
Cash, cash equivalents and restricted cash, end of period	489,095	260,726
Supplemental disclosures for cash flow information:
Cash paid (refund) for income taxes, net	(1,300)	244
Non-cash investing and financing activities:
Liability accrued for property and equipment purchases	2,482	6,122
Liability accrued for dividends and dividend equivalents	$ 49,219	$ 36,611