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Commitments and Contingencies - Additional Information (Detail) | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2015 USD ($) | Jun. 30, 2012 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2016 USD ($) Options | Dec. 31, 2015 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |
Rent expense under operating lease agreements |  |  |  | $ 1,000,000 | $ 1,100,000
Research and development expense |  |  |  | $ 21,577,000 | 23,243,000
Waltham [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Number of additional renewal terms | Options |  |  |  | 2 |
Additional operating lease term |  |  |  | 5 years |
Lexington [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Number of additional renewal terms | Options |  |  |  | 1 |
Additional operating lease term |  |  |  | 5 years |
Hydrogel License Agreement [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Research and development expense |  |  |  | $ 3,200,000 |
One-time payment amount |  |  | $ 3,000,000 | 3,000,000 |
Tissue Regeneration License Agreement [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Research and development expense |  |  |  | 700,000 |
One-time payment amount |  |  | 300,000 | $ 300,000 |
Percentage of royalty offsetting |  |  |  | 50.00% |
Maximum [Member] | Waltham [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Construction allowance to total cost of tenant improvements |  |  |  | $ 3,200,000,000 |
Maximum [Member] | Lexington [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Construction allowance to total cost of tenant improvements |  |  |  | 1,000,000 |
Minimum [Member] | Tissue Regeneration License Agreement [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Non-refundable royalty fee |  |  |  | 10,000 |
Tissue Processor Sub License Agreement [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Research and development expense |  |  |  | 1,000,000 |
Reimbursement for development cost |  | $ 300,000 |  |  |
Potential milestone payments |  |  | 10,200,000 | 10,200,000 |
Additional non-refundable royalty fee |  |  |  | $ 30,000 |
Additional non-refundable royalty fee payment description |  |  |  | 2016 through 2019 |
Tissue Processor Sub License Agreement [Member] | Minimum [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Non-refundable royalty fee |  |  |  | $ 20,000 |
Engineering Agreement [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Amount paid to suppliers |  |  | 200,000 | 600,000 |
Additional payments due |  |  | 0 | $ 0 |
Collagen Supply Agreement [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Minimum amount of material and/or services | $ 200,000 |  |  |  |
Non-refundable payment |  |  |  |  | $ 100,000
Initial term of the agreement | 3 years |  |  |  |
Supplier agreement description |  |  |  | The initial term of the agreement is three years and will automatically renew from year to year thereafter unless otherwise terminated with at least 180 days' notice by either party. |
OCS Agreement [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Accrued and received grants, aggregate |  |  | $ 1,100,000 | $ 1,100,000 |
OCS Agreement [Member] | Maximum [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Royalties payment, rate |  |  |  | 5.00% |
Royalty payment percentage as percentage of grant received |  |  |  | 300.00% |
OCS Agreement [Member] | Minimum [Member] |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |
Royalties payment, rate |  |  |  | 3.00% |
Royalty payment percentage as percentage of grant received |  |  |  | 100.00% |

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