The amount of a currency that the reporting entity is obligated to sell at settlement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Commitments and contingencies.

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No definition available.

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- Definition

Research and development grants.

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No definition available.

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- Definition

Average contractual rate at which a foreign currency can be purchased or sold.

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

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- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
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-Topic 730
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380

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Commitments and Contingencies - Additional Information (Detail) £ in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
	Sep. 30, 2017 GBP (£)	Dec. 31, 2008 GBP (£)	Sep. 30, 2017 USD ($) Contracts $ / £
Commitments And Contingencies [Line Items]
Research and development grant funding from Scottish Enterprise \| £		£ 1,791
Claims from grant \| £	£ 1,790
April 2018 through June 2018 [Member]
Commitments And Contingencies [Line Items]
Number of forward exchange contracts \| Contracts			3
Forward exchange contracts sold \| $			$ 500
Forward exchange contracts exchange rate pounds sterling to US dollar \| $ / £			1.2990
October 2017 through March 2018 [Member]
Commitments And Contingencies [Line Items]
Number of forward exchange contracts \| Contracts			6
Forward exchange contracts sold \| $			$ 500
Forward exchange contracts exchange rate pounds sterling to US dollar \| $ / £			1.2655