CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Operating activities:
Net loss	$ (217,292)	$ (253,210)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	11,301	11,665
Amortization of right-of-use operating lease assets	1,970	1,171
Amortization of patents	1,805	1,740
Amortization of premium on investments, net	9,072	13,515
Amortization of debt issuance costs	4,035	3,586
Stock-based compensation expense	74,575	98,419
Loss (gain) on investments	228	(933)
Loss on early retirement of debt	0	8,627
Non-cash losses related to disposal of property, plant and equipment	528	0
Non-cash losses related to patents	1,155	1,150
Changes in operating assets and liabilities:
Contracts receivable	55,251	67,136
Inventories	4,161	(965)
Other current and long-term assets	(988)	10,358
Income taxes payable	(20)	134
Accounts payable	5,607	(10,737)
Accrued compensation	(8,400)	(33,408)
Accrued liabilities and other current liabilities	38,263	(19,526)
Deferred contract revenue	(55,426)	(71,610)
Net cash used in operating activities	(74,175)	(172,888)
Investing activities:
Purchases of short-term investments	(1,223,791)	(930,963)
Proceeds from sale of short-term investments	764,101	1,051,857
Purchases of property, plant and equipment	(11,582)	(9,453)
Acquisition of licenses and other assets, net	(3,511)	(4,459)
Purchase of Bicycle Therapeutics plc common stock	0	(7,185)
Net cash (used in) provided by investing activities	(474,783)	99,797
Financing activities:
Proceeds from equity, net	6,030	11,564
Payments of tax withholdings related to vesting of employee stock awards and exercise of employee stock options	(10,217)	(16,285)
Proceeds from the issuance of 0 percent convertible notes	0	632,500
0 percent convertible senior notes issuance costs	0	(15,525)
Repurchase of $247.9 million principal amount of the 1 percent convertible senior notes	0	(256,963)
Proceeds from issuance of warrants	0	89,752
Purchase of note hedges	0	(136,620)
Principal payments on mortgage debt	(89)	0
Net cash (used in) provided by financing activities	(4,276)	308,423
Effects of exchange rates on cash	(964)	(43)
Net (decrease) increase in cash and cash equivalents	(554,198)	235,289
Cash and cash equivalents at beginning of period	869,191	397,664
Cash and cash equivalents at end of period	314,993	632,953
Supplemental disclosures of cash flow information:
Interest paid	2,204	3,527
Income taxes paid	2	3
Supplemental disclosures of non-cash investing and financing activities:
Amounts accrued for capital and patent expenditures	3,032	1,811
Right-of-use assets obtained in exchange for lease liabilities	$ 657	$ 0