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Income Taxes - Additional Information (Detail) | 3 Months Ended | 6 Months Ended
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Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Income Tax Disclosure [Abstract] |  |  |  |
Effective tax rate | 5.10% | 6.10% | 5.90% | 9.30%

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- Definition Effective tax rate continuing operations. + References No definition available. + Details
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- References No definition available. + Details
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