Cost of license and royalty revenue.

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- Definition

License agreement upfront payment.

+ References

No definition available.

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- Definition

License and royalty revenue.

+ References

No definition available.

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- Definition

Number of performance obligation identified at date of contract inception.

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No definition available.

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- Definition

Number of unsatisfied performance obligation identified at date of contract inception.

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No definition available.

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- Definition

Amount of billed or unbilled claims or other similar items subject to uncertainty concerning their determination or ultimate realization under long-term contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(c)(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of revenue earned from products sold or services provided under the terms of a contract, including, but not limited to, government contracts and construction contracts, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Costs incurred and are directly related to generating license revenue. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(e))
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Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

The amount of consideration recognized during the period for the milestone or milestones.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 28
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=68058744&loc=SL6892177-166501

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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
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License and royalty revenue - Additional Information (Detail)			1 Months Ended	3 Months Ended
	Apr. 28, 2017 USD ($) PerformanceObligation	Apr. 26, 2017 USD ($) PerformanceObligation	Aug. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
License And Royalty Revenue [Line Items]
Collaboration revenue				$ 15,608,000	$ 6,832,000
Cost of license and royalty revenue				17,000
Novartis Pharma AG [Member]
License And Royalty Revenue [Line Items]
License agreement upfront payment		$ 7,500,000
Revenue recognized upon achievement of a related milestone			$ 2,500,000
Royalty revenue				300,000	0
License revenue					0
Cost of license and royalty revenue					0
Novartis Pharma AG [Member] \| Maximum [Member]
License And Royalty Revenue [Line Items]
Cost of license revenue				100,000
Novartis Pharma AG [Member] \| Topic 606 [Member]
License And Royalty Revenue [Line Items]
Number of performance obligation identified at the date of contract inception \| PerformanceObligation		1
Collaboration revenue		$ 7,500,000
Novartis Pharma AG [Member] \| Topic 606 [Member] \| Regulatory Milestones Payments [Member]
License And Royalty Revenue [Line Items]
Collaboration revenue		2,500,000
Orchard Therapeutics Limited [Member]
License And Royalty Revenue [Line Items]
License agreement upfront payment	$ 3,000,000
Orchard Therapeutics Limited [Member] \| Topic 606 [Member]
License And Royalty Revenue [Line Items]
Number of performance obligation identified at the date of contract inception \| PerformanceObligation	1
License revenue				$ 0	$ 0
Number of unsatisfied performance obligation identified at date of contract inception \| PerformanceObligation	0
Regulatory Milestones Payments [Member] \| Novartis Pharma AG [Member]
License And Royalty Revenue [Line Items]
Amount per product eligible to be received upon achievement of specified event		7,500,000
Each Subsequently Licensed Product [Member] \| Novartis Pharma AG [Member]
License And Royalty Revenue [Line Items]
Amount per product eligible to be received upon achievement of specified event		$ 1,100,000
Potential Milestones Payments [Member] \| Orchard Therapeutics Limited [Member]
License And Royalty Revenue [Line Items]
Amount per product eligible to be received upon achievement of specified event	$ 1,300,000