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Income Taxes - Summary of Tax Years that Remain Subject to Examination by Major Jurisdiction (Detail) | 12 Months Ended
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Dec. 31, 2017
United States - Federal [Member] | Minimum [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2014
United States - Federal [Member] | Maximum [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
State and Local Jurisdiction [Member] | Minimum [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2012
Examination in progress | 2013
State and Local Jurisdiction [Member] | Maximum [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
Examination in progress | 2014
Foreign Tax Authority [Member] | Canada [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
Foreign Tax Authority [Member] | Germany [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
Foreign Tax Authority [Member] | Minimum [Member] | Canada [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2010
Examination in progress | 2014
Foreign Tax Authority [Member] | Minimum [Member] | Germany [Member] |
Income Tax Examination [Line Items] |
Examination in progress | 2012
Foreign Tax Authority [Member] | Minimum [Member] | France [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2014
Examination in progress | 2011
Foreign Tax Authority [Member] | Minimum [Member] | United Kingdom [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2015
Foreign Tax Authority [Member] | Minimum [Member] | Philippines [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2015
Foreign Tax Authority [Member] | Maximum [Member] | Canada [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2013
Examination in progress | 2015
Foreign Tax Authority [Member] | Maximum [Member] | Germany [Member] |
Income Tax Examination [Line Items] |
Examination in progress | 2015
Foreign Tax Authority [Member] | Maximum [Member] | France [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
Examination in progress | 2012
Foreign Tax Authority [Member] | Maximum [Member] | United Kingdom [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
Foreign Tax Authority [Member] | Maximum [Member] | Philippines [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016

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