Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating activities:
Net loss	$ (236,498)	$ (130,591)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,045	1,026
Amortization of intangibles	18,201	18,200
Intangible asset impairment charge	115,527	0
Amortization of premium/discount on investments	(2)	(685)
Non-cash interest expense	872	339
Non-cash operating lease expense	(1,164)	(1,097)
Fair value step-up of inventory sold or written off	31,116	33,587
Write-down of inventory	10,089	3,023
Change in excess inventory purchase commitments	10,954	0
Stock-based compensation	11,780	4,378
Deferred income taxes	0	(3,602)
Change in fair value of derivative liability	240	0
Changes in operating assets and liabilities:
Accounts receivable	(251)	(12,222)
Inventory	(5,680)	(17,188)
Prepaid expenses and other current assets	(3,277)	(11,337)
Other long-term assets	57	3,371
Accounts payable	(4,979)	(19,628)
Accrued expense	13,611	(28,126)
Operating lease liabilities	869	1,072
Deferred revenue	(14,879)	(16,815)
Net cash used in operating activities	(52,369)	(176,295)
Investing activities:
Purchase of equipment	(45)	(3,906)
Purchase of available for sale securities	(49,950)	0
Proceeds from the maturities of available for sale securities	245	103,691
Proceeds from sales of available for sale securities	0	64,721
Net cash provided by (used in) investing activities	(49,750)	164,506
Financing activities:
Proceeds from the issuance of common stock, net of issuance costs	198,883	9,035
Proceeds from the sale of stock under employee stock purchase plan	451	188
Proceeds from the exercise of stock options	821	560
Retirement of treasury stock	0	(426)
Payments on debt	0	(15,000)
Net cash provided by (used in) financing activities	200,155	(5,643)
Increase (decrease) in cash, cash equivalents, and restricted cash	98,036	(17,432)
Cash, cash equivalents, and restricted cash at beginning of the period	149,804	107,099
Cash, cash equivalents, and restricted cash at end of the period	247,840	89,667
Non-cash financing activities
Unpaid offering costs	$ 75	$ 0