Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating activities:
Net loss	$ (282,840)	$ (383,457)	$ (279,659)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,927	2,075	2,245
Amortization of intangibles	36,043	31,515	36,401
Intangible asset impairment charge	0	115,527	0
Non-cash interest expense related to sale of future royalties	9,117	0	0
Non-cash royalty revenue related to sale of future royalties	(821)	0	0
Amortization of premium/discount on investments	(15)	(47)	(819)
Non-cash interest expense	1,165	1,534	786
Non-cash operating lease expense	(1,842)	(2,037)	(2,229)
Write-off of property and equipment	0	0	2,053
Fair value step-up of inventory sold or written off	21,575	68,240	70,444
Write-down of inventory	15,618	20,072	7,112
Change in excess inventory purchase commitments	33,391	25,114	0
Stock-based compensation	22,735	24,460	11,925
Deferred income taxes	0	0	(6,631)
Change in fair value of derivative liability	(600)	286	0
Changes in operating assets and liabilities:
Accounts receivable	(24,022)	12,011	(22,198)
Inventory	(25,847)	6,163	(29,142)
Prepaid expenses and other current assets	(18,658)	(8,119)	10,541
Operating lease assets	(13,888)	0	0
Other long-term assets	5,674	(2,779)	4,917
Accounts payable	(11,735)	3,678	1,372
Accrued expense	(24,680)	6,356	(27,351)
Operating lease liabilities	15,398	1,411	2,531
Deferred revenue	1,821	(32,391)	(39,739)
Other non-current liabilities	(12,481)	0	0
Net cash used in operating activities	(252,965)	(110,388)	(257,441)
Investing activities:
Purchase of property and equipment	(59)	(317)	(6,655)
Purchase of available for sale securities	0	(99,932)	0
Proceeds from the maturities of available for sale securities	40,000	60,245	153,110
Proceeds from sales of available for sale securities	0	0	64,721
Net cash provided by (used in) investing activities	39,941	(40,004)	211,176
Financing activities:
Proceeds from sale of future royalties, net	44,783	0	0
Proceeds from the issuance of common stock, net of issuance costs	88,202	209,419	25,785
Proceeds from the sale of stock under employee stock purchase plan	746	1,100	383
Proceeds from the exercise of stock options	0	1,226	560
Retirement of treasury stock	0	0	(426)
Proceeds from the issuance of debt, net	0	19,975	77,668
Payments on debt	0	0	(15,000)
Net cash provided by financing activities	133,731	231,720	88,970
Increase (decrease) in cash, cash equivalents, and restricted cash	(79,293)	81,328	42,705
Cash, cash equivalents, and restricted cash at beginning of the period	231,132	149,804	107,099
Cash, cash equivalents, and restricted cash at end of the period	151,839	231,132	149,804
Non-cash financing activities
Unpaid offering costs	2	100	0
Cash paid for:
Interest	$ 9,632	$ 7,843	$ 781