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Income Taxes - Summary of Tax Years that Remain Subject to Examination by Major Jurisdiction (Detail) | 3 Months Ended
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Mar. 31, 2015
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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