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Income Taxes - Summary of Tax Years that Remain Subject to Examination by Major Jurisdiction (Detail) | 9 Months Ended
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Sep. 30, 2018
United States - State [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examination in progress | 2014
Foreign Tax Authority [Member] | France [Member] |
Income Tax Examination [Line Items] |
Examination in progress | 2012
Foreign Tax Authority [Member] | Philippines [Member] |
Income Tax Examination [Line Items] |
Examination in progress | 2016
Minimum [Member] | United States - Federal [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2015
Minimum [Member] | United States - State [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2013
Minimum [Member] | Foreign Tax Authority [Member] | Canada [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2010
Examination in progress | 2014
Minimum [Member] | Foreign Tax Authority [Member] | Germany [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
Examination in progress | 2011
Minimum [Member] | Foreign Tax Authority [Member] | France [Member] |
Income Tax Examination [Line Items] |
Examination in progress | 2015
Minimum [Member] | Foreign Tax Authority [Member] | United Kingdom [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2016
Minimum [Member] | Foreign Tax Authority [Member] | Philippines [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2015
Maximum [Member] | United States - Federal [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2017
Maximum [Member] | United States - State [Member] | United States [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2017
Maximum [Member] | Foreign Tax Authority [Member] | Canada [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2013
Examination in progress | 2017
Maximum [Member] | Foreign Tax Authority [Member] | Germany [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2017
Examination in progress | 2015
Maximum [Member] | Foreign Tax Authority [Member] | France [Member] |
Income Tax Examination [Line Items] |
Examination in progress | 2017
Maximum [Member] | Foreign Tax Authority [Member] | United Kingdom [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2017
Maximum [Member] | Foreign Tax Authority [Member] | Philippines [Member] |
Income Tax Examination [Line Items] |
Examinations not yet initiated | 2017

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