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Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended
--- | --- | ---
Jun. 30, 2012 | Mar. 31, 2019 | Mar. 31, 2018
Loss Contingencies [Line Items] |  |  |
Rent expense under operating lease agreements |  | $ 400 | $ 400
Operating Lease expense |  | 400 |
Variable executory cost |  | 300 |
Research and development expense |  | 1,583 | $ 3,286
Tissue Processor Sub License Agreement [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Research and development expense |  | 700 |
Reimbursement for development cost | $ 300 |  |
Additional non-refundable royalty fee |  | $ 30 |
Additional non-refundable royalty fee payment description |  | 2016 through 2019 |
Potential milestone payment |  | $ 10,200 |
Minimum [Member] | Tissue Processor Sub License Agreement [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Additional non-refundable royalty fee |  | 20 |
Hydrogel License Agreement [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Research and development expense |  | 3,200 |
Amount to be paid upon FDA approval |  | 3,000 |
Tissue Regeneration License Agreement [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Research and development expense |  | 800 |
Amount to be paid upon FDA approval |  | $ 300 |
Percentage of royalty offsetting |  | 50.00% |
Tissue Regeneration License Agreement [Member] | Minimum [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Non-refundable royalty fee |  | $ 10 |

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- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 730 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373 + Details
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