Commitments and Contingencies - Additional Information (Detail) $ in Thousands	Jun. 30, 2019 USD ($) Contracts $ / £
July 2019 through September 2019 [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 \| $ / £	1.30
October 2019 through December 2019 [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 \| $ / £	1.3180
January 2020 through March 2020 [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 \| $ / £	1.3245
April 2020 through June 2020 [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 \| $ / £	1.30

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.

+ References

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- Definition

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

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

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