Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other assets	$ 12,883	$ 9,824
Strategic Investments [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other assets	4,200	$ 4,400
Impairment charges	250
2022 Notes [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Fair value of notes	$ 597,800

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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-Topic 230
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-Section 45
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Fair value portion of notes payable.

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-SubTopic 10
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Amount of noncurrent assets classified as other.

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