Amount of revenue recognized that was previously reported as deferred or unearned revenue.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 13.A.4(a).Q1 Response))
-URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 55
-Paragraph 40
-Subparagraph (Note 3)
-URI http://asc.fasb.org/extlink&oid=82846649&loc=d3e38371-112697

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (a)
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- Definition

Distribution revenue reclassified as deferred revenue.

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- Definition

Increase in beginning and ending cash and cash equivalents and restricted cash due to adoption of new accounting guidance.

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Remaining term of distribution agreement.

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Significant accounting policies.

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Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands		3 Months Ended
	Aug. 31, 2016	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018
Significant Accounting Policies [Line Items]
Deferred revenue, recognized		$ 22,200	$ 400
Operating leases future minimum payments due		$ 1,879
ASU No. 2016-18
Significant Accounting Policies [Line Items]
Increase in cash, cash equivalents and restricted cash				$ 1,100
Itochu Corporation Agreement
Significant Accounting Policies [Line Items]
Remaining term of distribution agreement	8 years 6 months	8 years 6 months
Itochu Corporation Agreement \| Distribution Rights
Significant Accounting Policies [Line Items]
Distribution revenue reclassified as deferred revenue	$ 4,000	$ 4,000