CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Net income (loss)	$ (6,430,000)	$ 8,650,000
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation of property and equipment	323,000	345,000
Stock-based compensation	4,778,000	3,909,000
Amortization of premiums and accretion of discounts on marketable securities	77,000	490,000
Gain on sale of marketable securities	0	(12,000)
Intangible asset amortization	379,000	370,000
Deferred income taxes	4,417,000	1,160,000
Other non-cash adjustments, net	552,000	295,000
Changes in operating assets and liabilities:
Accounts receivable	1,957,000	(1,483,000)
Prepaid expenses and other assets	(13,360,000)	50,000
Inventory	(1,179,000)	42,000
Accounts payable and other liabilities	13,426,000	(5,272,000)
Product revenue allowances	(894,000)	649,000
Net cash provided by operating activities	4,046,000	9,193,000
Cash flows from investing activities
Purchases of property and equipment	(75,000)	(130,000)
Purchases of marketable securities	(79,134,000)	(93,060,000)
Sales and maturities of marketable securities	90,075,000	93,261,000
Net cash provided by investing activities	10,866,000	71,000
Cash flows from financing activities
Proceeds from exercise of stock options	0	1,849,000
Net cash provided by financing activities	0	1,849,000
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(57,000)	(15,000)
Net change in cash, cash equivalents and restricted cash	14,855,000	11,098,000
Cash, cash equivalents and restricted cash
Beginning of period	52,590,000	61,613,000
End of period	$ 67,445,000	$ 72,711,000