Stockholders' Equity - Summary of Restricted Stock Unit Activity (Detail) - Restricted Stock $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Number of Units outstanding, beginning of year (in shares) \| shares	1,655
Number of Units, Released (in shares) \| shares	(450)
Number of Units, Forfeited (in shares) \| shares	(410)
Number of Units outstanding, end of period (in shares) \| shares	7,271
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Units outstanding, beginning of year (in dollars per share)	$ 28.34
Weighted Average Grant Date Fair Value, Granted (in dollars per share)	35.87
Weighted Average Grant Date Fair Value, Released (in dollars per share)	24.47
Weighted Average Grant Date Fair Value, Forfeited (in dollars per share)	34.63
Weighted Average Grant Date Fair Value, Units outstanding, end of period (in dollars per share)	$ 34.93
Aggregate intrinsic value at end of period \| $	$ 412,866

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
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-Topic 718
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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No definition available.

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