Income Taxes - Schedule of Future Payments Under Tax Benefit Arrangements (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Remainder of 2019	$ 7,307
2020	25,965
2021	26,584
2022	27,141
2023	27,679
Thereafter	318,714
Total	$ 433,390	$ 429,233

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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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