Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Operating activities:
Net loss	$ (14,511)	$ (15,199)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Stock-based compensation	26,583	17,424
Revaluation of common stock warrant liability to estimated fair value	(50)	990
Depreciation and amortization	6,301	5,052
Unrealized loss on long-term marketable equity securities	167	0
Revaluation of contingent consideration to estimated fair value	(35)	301
Amortization of premium on short-term marketable securities, net	930	0
Changes in operating assets and liabilities:
Accounts receivable	(21,580)	(5,359)
Inventory	(9,417)	(3,608)
Prepaid and other assets	(2,072)	(681)
Operating leases liabilities, net	(1,677)	(1,096)
Accounts payable	400	3,831
Accrued compensation	2,711	1,501
Accrued and other liabilities	7,688	1,581
Refund liability - CMS advance payment	(20,496)	20,496
Change in deferred taxes	(589)	(879)
Net cash (used in) provided by operating activities	(23,460)	26,250
Investing activities:
Acquisition of business, net of cash acquired	(3,500)	0
Acquisition of intangible assets	(6,700)	(3,250)
Purchases of long-term marketable securities	(5,500)	0
Maturities of short-term marketable securities	78,905	0
Additions of capital expenditures, net	(7,711)	(6,670)
Net cash provided by (used in) investing activities	55,494	(9,920)
Financing activities:
Proceeds from issuance of common stock under employee stock purchase plan	2,139	1,082
Taxes paid related to net share settlement of restricted stock units	(15,376)	(4,003)
Proceeds from exercise of warrants	4	343
Proceeds from exercise of stock options	10,920	3,764
Principal payments on finance lease obligations	(66)	(136)
Net cash provided by financing activities	186,476	159,185
Effect of exchange rate changes on cash and cash equivalents	(157)	64
Net increase in cash, cash equivalents and restricted cash	218,353	175,579
Cash, cash equivalents, and restricted cash at beginning of period	134,939	38,479
Cash, cash equivalents, and restricted cash at end of period	353,292	214,058
Operating Lease, Right-of-Use Asset, Amortization Expense	2,187	1,896
Public Offering
Financing activities:
Proceeds from issuance of common shares in net of issuance costs paid	188,855	134,684
At The Market Equity Offering
Financing activities:
Proceeds from issuance of common shares in net of issuance costs paid	$ 0	$ 23,451