Income Tax Expense (Recovery) - Unrecognized Tax Benefits, Recorded in Other Long-Term Liabilities (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 40,556	$ 31,061
Unrecognized Tax Benefits, Increase Resulting from Settlements with Taxing Authorities	3,213	2,908
Increases for positions related to the current year	3,066	2,161
Decrease related to statute of limitations	0	405
Ending balance	$ 46,835	$ 35,725

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Section 50
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- Definition

Amount of increase in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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