Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net cash flows from operating activities:
Net (loss) income	$ (16,682)	$ 1,720	$ (2,840)
Adjustments to reconcile net (loss) income to net cash from operating activities:
Depreciation and amortization	20,712	18,317	18,095
Non-cash lease expense	7,145	5,009
Non-cash compensation	6,912	8,799	6,325
Change in fair value of long-term loan receivable	4,949
Change in fair value of contingent consideration	4,523
Deferred income taxes	4,283	(2,305)	(4,485)
Write-down of inventories and deferred preservation costs	3,443	1,488	649
Other	3,780	2,182	2,149
Changes in operating assets and liabilities:
Receivables	9,938	(5,332)	(1,119)
Prepaid expenses and other assets	(2,720)	(6,177)	(2,407)
Accounts payable, accrued expenses, and other liabilities	(9,157)	251	(8,870)
Inventories and deferred preservation costs	(24,757)	(8,125)	2,384
Net cash flows provided by operating activities	12,369	15,827	9,881
Net cash flows used in investing activities:
Ascyrus Acquisition, net of cash acquired	(59,119)
Capital expenditures	(7,328)	(8,072)	(5,786)
Payments for Endospan Agreements	(5,000)	(15,000)
Other	(1,681)	(871)	(929)
Net cash flows used in investing activities	(73,128)	(23,943)	(6,715)
Net cash flows from financing activities:
Proceeds from issuance of convertible debt	100,000
Proceeds from revolving line of credit	30,000
Proceeds from financing insurance premiums	2,815
Proceeds from exercise of stock options and issuance of common stock	2,432	4,758	3,854
Repayment of revolving line of credit	(30,000)
Repayment of debt	(5,346)	(2,780)	(2,790)
Payment of debt issuance costs	(3,647)		(624)
Redemption and repurchase of stock to cover tax withholdings	(1,995)	(2,743)	(2,100)
Other	(651)	(728)	(902)
Net cash flows provided by (used in) financing activities	93,608	(1,493)	(2,562)
Effect of exchange rate changes on cash	(5,185)	1,667	879
Increase (decrease) in cash, cash equivalents, and restricted securities	27,664	(7,942)	1,483
Cash, cash equivalents, and restricted securities, beginning of year	34,294	42,236	40,753
Cash, cash equivalents, and restricted securities, end of year	$ 61,958	$ 34,294	$ 42,236