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Income Taxes Recognized During Period (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
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Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Income Tax Disclosure [Abstract] |  |  |  |
Provision for income taxes | $ 9,212 | $ 11,550 | $ 19,862 | $ 23,175
Tax impact of restructuring and other items | (1,453) | (969) | (1,453) | (969)
Tax impact of restructuring and other items | $ 7,759 | $ 10,581 | $ 18,409 | $ 22,206

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