Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flow from operating activities:
Net income	$ 111,002	$ 79,666
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	21,140	25,773
Provision for credit losses	230	493
Loss on disposal of property and equipment	0	5
Loss on non-marketable securities	533	0
Stock-based compensation, net of amounts capitalized	50,560	37,856
Amortization (accretion) of premiums (discount) on marketable securities, net	(3,502)	1,127
Deferred income taxes	(11,561)	(15,599)
Changes in operating assets and liabilities:
Accounts receivable	18,137	9,788
Prepaid expenses and other assets	(4,804)	(1,412)
Accounts payable	(1,428)	841
Accrued liabilities and other noncurrent liabilities	8,211	3,968
Deferred revenues	22,248	12,504
Net cash provided by operating activities	210,766	155,010
Cash flow from investing activities:
Purchases of marketable securities	(252,438)	(178,788)
Sales and maturities of marketable securities	212,202	290,949
Purchases of property and equipment	(7,263)	(12,391)
Purchases of intangible assets	0	(120)
Net cash (used in) provided by investing activities	(47,499)	99,650
Cash flow from financing activities:
Repurchase of common stock	(147,725)	(212,839)
Proceeds from exercise of stock options	28,384	23,161
Payments for taxes related to net share settlement of equity awards	(14,998)	(12,853)
Proceeds from issuance of common stock through employee stock purchase plan	6,077	4,445
Net cash used in financing activities	(128,262)	(198,086)
Net increase in cash, cash equivalents and restricted cash	35,005	56,574
Cash, cash equivalents and restricted cash at beginning of period	176,419	138,528
Cash, cash equivalents and restricted cash at end of period	$ 211,424	$ 195,102