Income Taxes - Summary of Significant Tax Jurisdictions Currently under Audit (Detail)	12 Months Ended
Dec. 31, 2015
Canada [Member]
Income Tax Examination [Line Items]
Significant tax jurisdictions currently under audit	2003 to 2009

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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