Equity-Based Compensation - Weighted-Average Fair Value of Stock Options and Employee Stock Purchase Rights using Weighted-Average Assumptions (Detail) - $ / shares	3 Months Ended
Mar. 28, 2020	Mar. 30, 2019
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of grants per share	$ 1.82	$ 2.28
Expected volatility	46.06%	43.40%
Risk free interest rate	0.44%	2.21%
Expected term of options (in years)	4 years 4 months 20 days	4 years 3 months 25 days
Dividend yield	0.00%	0.00%
Stock Purchase Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value of grants per share	$ 1.66	$ 1.89
Expected volatility	36.69%	50.00%
Risk free interest rate	1.56%	2.53%
Expected term of options (in years)	6 months	1 year
Dividend yield	0.00%	0.00%

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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

+ Details

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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