Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (215,584)	$ (254,411)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	4,972	5,111
Stock-based compensation	43,876	75,037
Accretion of investment discounts	(3,947)	(9,934)
Recognition of equity method investment intra-entity profit on sales	0	(20,967)
Change in fair value of investments, net	786	26,419
Changes in operating assets and liabilities:
Accounts receivable	(2,836)	24,128
Prepaid expenses and other current assets	5,373	(6,239)
Operating lease right-of-use assets	16,151	9,963
Other assets	(24,415)	1,493
Accounts payable	(4,431)	10,916
Accrued expenses	(13,583)	(20,555)
Deferred revenue	(9,224)	(10,757)
Operating lease liabilities	(45,690)	(9,052)
Net cash used in operating activities	(248,552)	(178,848)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(974)	(3,518)
Purchases of marketable securities	(138,809)	(560,368)
Sales and maturities of marketable securities	341,021	545,597
Net cash provided by (used in) investing activities	201,238	(18,289)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from options exercised	0	3,137
Issuance of shares through employee stock purchase plan	1,237	1,669
Net cash provided by financing activities	14,652	101,238
Net decrease in cash, cash equivalents and restricted cash equivalents	(32,662)	(95,899)
Cash, cash equivalents and restricted cash equivalents, beginning of period	202,787	240,353
Cash, cash equivalents and restricted cash equivalents, end of period	170,125	144,454
Reconciliation of cash, cash equivalents and restricted cash equivalents to condensed consolidated balance sheet:
Cash and cash equivalents	156,172	130,849
Restricted cash equivalents, included in prepaid expenses and other current assets,and investments and other assets	13,953	13,605
Total cash, cash equivalents and restricted cash equivalents	170,125	144,454
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Purchases of property and equipment unpaid at period end	0	631
Reduction of right-of-use assets from remeasurement of lease liabilities	61,917	0
Proceeds from at-the-market offerings unpaid at period end	307	0
At The Market Offerings [Member]
CASH FLOWS FROM FINANCING ACTIVITIES:
Net proceeds from issuance of common stock through at-the-market offerings	$ 13,415	$ 96,432