Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities
Net income (loss)	$ (280,321)	$ 127,840	$ (111,250)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities
Stock-based compensation expense	40,788	38,808	31,949
Depreciation and amortization	12,909	9,564	8,407
Provision for credit losses (recoveries)	0	(2,569)	7,678
Net amortization of premiums on marketable debt securities	4,712	5,842	1,083
Net loss (gain) on investments	79	(5,189)	(4,918)
Imputed interest income from licensing	(342)	(360)	(2,163)
Non-cash interest expense	137	4,642	771
Other non-cash adjustments	573	79	163
Changes in operating assets and liabilities
Accounts receivable	4,822	14,118	(9,898)
Prepaid expenses	4,852	(8,247)	(4,030)
Other current assets	247	(7,314)	2,341
Operating lease right-of-use assets	4,450	4,866	3,219
Other assets	31	(2,272)	399
Accounts payable	18,790	(2,304)	3,873
Accrued expenses and other current liabilities	(25,616)	29,908	17,400
Deferred revenue	(1,165)	(899)
Operating lease liabilities	(544)	12,073	2,139
Other liabilities	8,110	289	(1,224)
Net cash provided by (used in) operating activities	(207,488)	218,875	(54,061)
Cash flows from investing activities
Purchases of marketable debt securities	(184,875)	(498,144)	(123,041)
Maturities of marketable debt securities	203,146	170,086	233,468
Sales of marketable debt securities			2,287
Sales of equity securities	524	5,591	36,914
Purchases of property and equipment	(30,724)	(84,175)	(26,869)
Net cash provided by (used in) investing activities	(11,929)	(406,642)	122,759
Cash flows from financing activities
Proceeds from exercise of stock options	2,804	4,281	5,623
Taxes paid related to net settlement of stock-based awards	(284)	(2)
Proceeds from issuance of common stock under employee stock purchase plan	1,742	1,768	1,799
Proceeds from public offering of common stock, net of underwriting discounts and commissions		216,438
Issuance costs for public offering of common stock		(379)
Proceeds from sale of future royalties			196,000
Transaction costs for sale of future royalties		(265)	(3,208)
Repayments under liability related to sale of future royalties, net of imputed interest	(33,102)	(26,591)
Net cash provided by (used in) financing activities	(28,840)	195,250	200,214
Net increase (decrease) in cash and cash equivalents and restricted cash	(248,257)	7,483	268,912
Cash and cash equivalents and restricted cash
Beginning of period	347,239	339,756	70,844
End of period	98,982	347,239	339,756
Supplemental cash flow information
Cash paid (received) for income taxes	11,812	5,996	$ (191)
Cash paid for imputed interest under liability related to sale of future royalties	$ 23,117	$ 21,635