Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net loss	$ (135,682)	$ (44,815)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	1,806	1,811
Stock-based compensation	8,690	7,177
Amortization of debt issuance costs	726	708
Asset Impairment Charges	1,600	0
Changes in operating assets and liabilities:
(Increase) decrease in accounts receivable	25,656	344
(Increase) decrease in inventory	254	403
(Increase) decrease in prepaid expenses and other current assets	(4,141)	(3,957)
Decrease in other assets	207	186
Decrease in accounts payable and other liabilities	32,532	(13,842)
Decrease in deferred revenue	0	(535)
Net cash provided by (used in) operating activities	(68,352)	(52,520)
Cash flows from investing activities:
Purchases of property and equipment	0	(70)
Purchases of investments	(37,148)	(106,706)
Maturities of investments	158,000	91,600
Net cash (used in) provided by investing activities	120,852	(15,176)
Cash flows from financing activities:
Repurchase of common stock	(1,026)	(941)
Repayment of debt borrowings, net of fees	(643)	(643)
Net cash used in financing activities	(1,669)	(1,584)
Net increase (decrease) in cash and cash equivalents	50,831	(69,280)
Cash and cash equivalents at beginning of period	36,112	80,386
Cash and cash equivalents at end of period	86,943	11,106
Supplemental disclosure of cash flow information:
Cash paid for interest	$ 9,569	$ 9,610