Stock-Based Compensation - Schedule of Stock Compensation Activity (Detail) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based compensation expense recognized	$ 39,792,000	$ 37,034,000	$ 26,326,000
Tax benefit recognized	14,806,000	32,511,000
Tax benefit recognized			27,867,000
Stock-based compensation expense capitalized	$ 0	$ 0	$ 0

Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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No definition available.

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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

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-Name Accounting Standards Codification
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-Paragraph 2
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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-Publisher FASB
-Name Accounting Standards Codification
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