Income Tax (Expense) Recovery - Unrecognized Tax Benefits, Recorded in Other Long-Term Liabilities (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2014 USD ($)
Income Tax Disclosure [Abstract]
Balance of unrecognized tax benefits as at January 1, 2015	$ 20,335
Increase for positions related to the current period	1,802
Decrease related to statute of limitations	(1,447)
Balance of unrecognized tax benefits as at June 30, 2015	$ 20,690

No definition available.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

+ Details

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

+ Details

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- Definition

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

+ References

+ Details

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