Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating activities:
Net loss	$ (182,024,000)	$ (220,683,000)
Adjustments to reconcile net loss to net cash used for operating activities:
Stock-based compensation expense	42,980,000	46,851,000
Depreciation and amortization	2,889,000	3,021,000
Amortization of debt discount		785,000
Amortization of debt issuance costs	202,000	119,000
Amortization of premium (accretion of discount) on short-term investments	(736,000)	332,000
Realized gain on available-for-sale investments	0	0
Impairment of property and equipment	209,000	478,000
Loss on disposal of property and equipment	74,000	822,000
Change in operating assets and liabilities:
Accounts receivable	(16,550,000)	6,351,000
Inventory	(6,191,000)	(6,477,000)
Prepaid expenses and other assets	1,010,000	(8,386,000)
Accounts payable	(578,000)	3,278,000
Accrued clinical and manufacturing liabilities	752,000	(26,246,000)
Accrued payroll and employee liabilities	(1,847,000)	1,666,000
Other accrued liabilities	12,898,000	(5,265,000)
Net cash used in operating activities	(146,912,000)	(203,354,000)
Investing activities:
Purchases of short-term investments	(145,683,000)	(129,221,000)
Maturities and sales of short-term investments	143,957,000	164,940,000
Purchases of property and equipment	(1,825,000)	(3,022,000)
Proceeds from the sale of property and equipment	227,000	32,000
Net cash provided by (used in) investing activities	(3,324,000)	32,729,000
Financing activities:
Net proceeds from sale of common stock	75,145,000
Net proceeds from convertible notes financing		148,963,000
Proceeds from purchases under the Employee Stock Purchase Plan	1,444,000	2,139,000
Proceeds from (payments for) stock issued under the equity incentive plan	(1,530,000)	4,926,000
Net cash provided by financing activities	75,059,000	156,028,000
Net decrease in cash and cash equivalents	(75,177,000)	(14,597,000)
Cash and cash equivalents at beginning of year	90,541,000	105,138,000
Cash and cash equivalents at end of year	15,364,000	90,541,000
Supplemental disclosure of cash flow information:
Interest paid	$ 2,250,000	$ 1,244,000