Lessee operating lease number of option to extend.

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- Definition

Lessee operating lease period of contract.

+ References

No definition available.

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- Definition

Liabilities for additional milestone payment.

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No definition available.

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- Definition

Non-refundable cash payment.

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No definition available.

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- Definition

Number of milestones achieved.

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No definition available.

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- Definition

Operating lease base rent per year.

+ References

No definition available.

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- Definition

Operating lease price per square foot per year.

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No definition available.

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- Definition

Payments for milestone.

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No definition available.

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- Definition

Area of land held.

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No definition available.

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- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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No definition available.

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 2
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- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
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- Definition

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 20
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- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Net cash outflow for the allowance granted to lessee and/or direct costs incurred by lessor used to prepare the leased premises for tenant's occupancy; for costs that are essential to originating the lease and would not otherwise have been incurred without the lease agreement, including but not limited to, evaluating the lessee's credit condition, guarantees, and collateral and costs incurred in negotiating, processing, and executing the lease agreement; and for any commission(s) incurred.

+ References

No definition available.

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- Definition

The amount of cash paid for royalties during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

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Commitments and Contingencies - Additional Information (Detail)		1 Months Ended		3 Months Ended		12 Months Ended
	Apr. 04, 2018 USD ($) ft² $ / ft²	Oct. 31, 2010 USD ($)	Feb. 28, 2010 USD ($)	Mar. 31, 2019 USD ($) Option Milestone	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2006 USD ($)
Other Commitments [Line Items]
Operating lease, right-of-use asset				$ 6,543,000
Operating lease, liability				$ 5,316,000
ASU No. 2016-02 [Member]
Other Commitments [Line Items]
Operating lease, right-of-use asset							$ 6,697,000
Operating lease, liability							$ 5,401,000
Operating Lease Agreements [Member] \| Building [Member]
Other Commitments [Line Items]
Lessee, Operating Lease, Existence of Option to Extend [true false]				true
Lessee Operating Lease Option To Extend				The Company has the option to extend the 490 Arsenal Way Lease for one five-year terms.
Harvard and Dana-Farber Agreement [Member]
Other Commitments [Line Items]
Milestone payments				$ 0	$ 0
Milestones achieved \| Milestone				0
Additional liabilities for milestone payments				$ 0
Non-refundable cash payment				4,718,000		$ 4,573,000
Payments for royalties				0
Harvard and Dana-Farber Agreement [Member] \| Therapeutic Product [Member]
Other Commitments [Line Items]
Aggregate milestones payments			$ 7,700,000
Harvard and Dana-Farber Agreement [Member] \| Diagnostic Product [Member]
Other Commitments [Line Items]
Aggregate milestones payments			700,000
Harvard and Dana-Farber Agreement [Member] \| License and Maintenance [Member]
Other Commitments [Line Items]
Annual license maintenance fees			$ 145,000
Harvard and Dana-Farber Agreement [Member] \| License [Member]
Other Commitments [Line Items]
Annual license maintenance fees				145,000	145,000
Umicore Agreement [Member]
Other Commitments [Line Items]
Aggregate milestones payments								$ 6,400,000
Milestone payments				$ 0	0
Milestones achieved \| Milestone				0
Additional liabilities for milestone payments				$ 0
Umicore Agreement [Member] \| License and Maintenance [Member]
Other Commitments [Line Items]
Annual license maintenance fees				50,000
Umicore Agreement [Member] \| License [Member]
Other Commitments [Line Items]
Annual license maintenance fees				$ 50,000	0
Scripps Agreement [Member]
Other Commitments [Line Items]
Milestones achieved \| Milestone				0
Additional liabilities for milestone payments				$ 0
Payments for royalties				0
Scripps Agreement [Member] \| License and Maintenance [Member]
Other Commitments [Line Items]
Annual license maintenance fees		$ 50,000
Scripps Agreement [Member] \| License [Member]
Other Commitments [Line Items]
Annual license maintenance fees				$ 0	$ 0
Scripps Agreement [Member] \| Peptide Product [Member]
Other Commitments [Line Items]
Aggregate milestones payments		1,900,000
Scripps Agreement [Member] \| Protein Product [Member]
Other Commitments [Line Items]
Aggregate milestones payments		$ 950,000
Watertown, Massachusetts [Member] \| Operating Lease Agreements [Member] \| 490 Arsenal Way [Member] \| Building [Member]
Other Commitments [Line Items]
Area of Land \| ft²	18,768
Operating lease price per square foot per year \| $ / ft²	52.55
Base rent per year	$ 986,000
Security deposit	568,000
Cost of construction and tenant improvements	$ 2,419,000
Period of contract				Aug. 31, 2026
Number of option to extend \| Option				1
Lease initial term				8 years
Lease extension term				5 years
Building in service over a useful life				30 years