Interim Consolidated Financial Statements - Summary of Allowance for Expected Credit Losses on Accounts Receivable (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2020 USD ($)
Receivables [Abstract]
Balance at December 31, 2019	$ 628
Cumulative effect adjustment of adopting Topic 326	218
Provision for expected credit losses	591
Write-offs	(637)
Translation adjustments	(4)
Balance at September 30, 2020	$ 796

Accounts receivable, allowance for credit loss, translation adjustments.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable from change in methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919244-210447

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446

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Balance Type:	credit
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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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- References

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