Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating activities
Net income	$ 94,603	$ 3,563
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	1,355	1,365
Stock-based compensation expense	18,980	17,486
Non-cash accretion of discount on marketable securities		(127)
Non-cash interest expense from amortization of debt discount	1,523	1,127
Excess and obsolete inventory		410
Other non-cash adjustments	326	4
Non-cash operating lease expense	1,038	818
Upfront license fee payment to Innovent	5,000
Changes in operating assets and liabilities:
Trade receivables, net	(30,677)	(77,385)
Inventory	(25,236)	(16,706)
Prepaid manufacturing	(5,577)	1,158
Other prepaid and current assets	(947)	(2,630)
Other assets, non-current	(1,275)
Accounts payable	(5,132)	4,074
Accrued rebates, fees and reserve	15,109	20,650
Accrued compensation	(2,863)	1,620
Accrued and other liabilities	7,761	1,317
Lease liabilities	(320)	(1,020)
Other liabilities, non-current		(30)
Net cash provided by (used in) operating activities	73,668	(44,306)
Investing activities
Purchases of property and equipment	(4,167)	(517)
Proceeds from disposal of property and equipment	167
Purchases of investments in marketable securities	(231,864)	(14,864)
Proceeds from maturities of investments in marketable securities		9,000
Upfront license fee payment to Innovent	(5,000)
Net cash used in investing activities	(240,864)	(6,381)
Financing activities
Proceeds from common stock offering, net of underwriters discounts, commissions and offering costs		8,153
Proceeds from issuance of Convertible Notes due 2026, net of issuance costs	222,830
Purchase of capped call options related to Convertible Notes due 2026	(18,170)
Proceeds from term loan, net of issuance costs		73,061
Proceeds from issuance of common stock upon exercise of stock options	8,105	1,395
Proceeds from purchase under the employee stock purchase plan	2,557	1,878
Taxes paid related to net share settlement of bonus payout in RSUs	(880)
Other financing activities	(97)
Net cash provided by financing activities	214,345	84,487
Effect of exchange rate changes in cash, cash equivalents and restricted cash		(229)
Net increase in cash, cash equivalents and restricted cash	47,149	33,571
Cash, cash equivalents and restricted cash at beginning of period	177,908	73,191
Cash, cash equivalents and restricted cash at end of period	225,057	106,762
Supplemental disclosure of cash flow information
Non-cash bonus payment settled in common stock	1,498	$ 1,350
Right-of-use assets obtained in exchange for lease obligations related to operating leases	1,388
Right-of-use assets obtained in exchange for lease obligations related to finance leases	$ 1,528