Employee Stock-Based Compensation - Restricted Stock Unit Valuation (Detail) - Performance Market and Service Condition Based Restricted Stock Unit Grants	9 Months Ended
Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility (company)	40.00%
Expected volatility (peer group median)	40.00%
Correlation between the company and peer group median	0.5
Expected dividend yield	0.00%
Risk-free rate	0.90%

The correlation coefficient between the company and the peer group median.

No definition available.

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- Definition

The estimated measure of the percentage by which the share prices of the constituents of the peer group is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

+ Details

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) over the vesting period.

+ References

No definition available.

+ Details

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- Definition

The risk-free interest rate assumption that is used in valuing restricted stock units.

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No definition available.

+ Details

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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 (f)(2)(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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