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Income Taxes - Summary of Tax Years that Remain Subject to Examination by Major Jurisdiction (Detail)	12 Months Ended
	Dec. 31, 2014
United States - Federal [Member]
Income Tax Examination [Line Items]
Examinations not yet initiated	2013 - 2014
Examination in progress	2011 - 2012
United States - State [Member]
Income Tax Examination [Line Items]
Examinations not yet initiated	2010 - 2014
Examination in progress	2011 - 2012
Canada [Member]
Income Tax Examination [Line Items]
Examinations not yet initiated	2010 - 2014
Examination in progress	2009
Germany [Member]
Income Tax Examination [Line Items]
Examinations not yet initiated	2012 - 2014
Examination in progress	2007 - 2011
France [Member]
Income Tax Examination [Line Items]
Examinations not yet initiated	2013 - 2014
Examination in progress	2011 - 2012
United Kingdom [Member]
Income Tax Examination [Line Items]
Examinations not yet initiated	2013 - 2014
Examination in progress	N/A
Philippines [Member]
Income Tax Examination [Line Items]
Examinations not yet initiated	2012 - 2014
Examination in progress	2011

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