Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Operating activities:
Net loss	$ (60,747)	$ (72,421)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	525	439
Amortization of intangibles	9,100	9,100
Amortization of premium/discount on investments		(477)
Non-cash interest expense	437	169
Non-cash operating lease expense	(647)	(614)
Fair value write-up of inventory sold	11,180	14,586
Write-down of inventory	139	1,664
Stock-based compensation	4,916	2,094
Deferred income taxes		(2,757)
Change in fair value of derivative liability	90
Changes in operating assets and liabilities:
Accounts receivable	(66,008)	(31,769)
Inventory	(8,163)	(16,064)
Prepaid expenses and other current assets	(1,898)	1,317
Other long-term assets	46	719
Accounts payable	20,470	(20,746)
Accrued expense	(4,209)	(17,500)
Operating lease liabilities	445	549
Deferred revenue	4,735	(6,218)
Net cash used in operating activities	(89,589)	(137,929)
Investing activities:
Purchase of equipment		(1,928)
Proceeds from the maturities of available for sale securities	245	78,691
Proceeds from sales of available for sale securities		33,710
Net cash provided by investing activities	245	110,473
Financing activities:
Proceeds from the issuance of common stock, net of issuance costs	56,485
Proceeds from the sale of stock under employee stock purchase plan	451	188
Proceeds from the exercise of stock options	412	365
Payments on debt		(15,000)
Net cash provided by financing activities	57,348	(14,447)
Increase in cash, cash equivalents, and restricted cash	(31,996)	(41,903)
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	117,808	$ 65,196
Non-cash financing activities
Unpaid offering costs	$ 90