Income Taxes - Schedule of Future Payments Under Tax Benefit Arrangements (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Remainder of 2018	$ 8,764
2019	24,004
2020	23,983
2021	24,407
2022	24,897
Thereafter	311,399
Total	$ 417,454	$ 431,360

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Income taxes projected future payments under tax benefit arrangements liability remainder of fiscal year.

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Income taxes projected future payments under tax benefit arrangements liability year five.

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Income taxes projected future payments under tax benefit arrangements liability year four.

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Income taxes projected future payments under tax benefit arrangements liability year thereafter.

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Income taxes projected future payments under tax benefit arrangements liability year three.

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Income taxes projected future payments under tax benefit arrangements liability year two.

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