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Commitments and Contingencies (Details) - USD ($) $ in Thousands |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | ---
Oct. 29, 2018 | Aug. 31, 2018 | Feb. 27, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2019 | Apr. 27, 2018
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |  |
Contractual obligation, due in next twelve months |  |  |  | $ 8,653 |  |  |
Contractual obligation |  |  |  | 14,743 |  |  |
Initial term of lease |  |  | 63 months |  |  |  |
Lease commencement date |  |  | Jan. 01, 2018 |  |  |  |
Buy-out of obligations lease |  |  | $ 600 |  |  |  |
Common stock, aggregate amount |  |  |  | $ 0 | $ 0 | $ 0 |
Lorem Vascular [Member] |  |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |  |
Percentage of common stock to be purchased |  |  |  |  |  |  | 5.00%
Common stock, aggregate amount |  |  |  |  |  |  | $ 5,000
Amended complaint dismissal date |  |  |  | Oct. 01, 2018 |  |  |
Bimini Technologies LLC | Demand for Arbitration [Member] | Sale and Exclusive License/Supply Agreement [Member] |  |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |  |
Potential milestone payment due upon acheivement of gross profit |  | $ 1,000 |  |  |  |  |
Gross profit from sale of company’s puregraft product line |  | 10,000 |  |  |  |  |
Potential milestone payment claimed |  | $ 1,000 |  |  |  |  |
Proceeds from milestone payment | $ 1,000 |  |  |  |  |  |
Pre-clinical Research Study Obligations [Member] |  |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |  |
Contractual obligation, due in next twelve months |  |  |  | $ 1,800 |  | 1,800 |
Contractual obligation |  |  |  | 3,000 |  | $ 2,500 |
Operating Lease Obligations [Member] |  |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |  |
Rent expense |  |  |  | $ 1,400 | $ 1,600 |  |

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