Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss			$ (254,411)	$ (226,807)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization			5,111	4,220
Loss on disposal of property and equipment			0	15
Stock-based compensation			75,037	63,655
Accretion of investment discounts and premiums			(9,934)	(11,667)
(Recognition) deferral of equity method investment intra-entity profit on sales			(20,967)	5,656
Change in fair value of investments	$ 20,354	$ 0	26,419	0
Loss from equity method investment	0	4,000	0	7,048
Change in fair value of contingent consideration	0	0	0	100
Changes in operating assets and liabilities:
Accounts receivable			24,128	(1,289)
Prepaid expenses and other current assets			(6,239)	(6,078)
Operating lease right-of-use assets			9,963	9,373
Other assets			1,493	(503)
Accounts payable			10,916	6,287
Accrued expenses			(20,555)	(12,525)
Deferred revenue			(10,757)	(28,919)
Operating lease liabilities			(9,052)	(8,217)
Net cash used in operating activities			(178,848)	(199,651)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment			(3,518)	(8,133)
Purchases of marketable securities			(560,368)	(625,319)
Sales and maturities of marketable securities			545,597	476,666
Net cash used in investing activities			(18,289)	(156,786)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from options exercised			3,137	1,220
Issuance of shares through employee stock purchase plan			1,669	2,051
Net cash provided by financing activities			101,238	4,737
Net decrease in cash, cash equivalents and restricted cash equivalents			(95,899)	(351,700)
Cash, cash equivalents and restricted cash equivalents, beginning of period			240,353	535,463
Cash, cash equivalents and restricted cash equivalents, end of period	144,454	183,763	144,454	183,763
Reconciliation of cash, cash equivalents and restricted cash equivalents to condensed consolidated balance sheet:
Cash and cash equivalents	130,849	171,806	130,849	171,806
Restricted cash equivalents, included in investments and other assets	13,605	11,957	13,605	11,957
Total cash, cash equivalents and restricted cash equivalents	144,454	183,763	144,454	183,763
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Purchases of property and equipment unpaid at period end			631	2,998
Shares issued for Rewrite contingent consideration	$ 0	$ 24,126	0	24,126
At The Market Offerings [Member]
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock through at-the-market offerings			$ 96,432	$ 1,466