Maximum employee salary withholdings for purchase of common stock under the terms of the ESSP.

No definition available.

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- Definition

Number of participants that received awards associated with the annual bonus program.

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No definition available.

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- Definition

Employee stock purchase plan (ESPP), purchase period.

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No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award, award conversion ratio.

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No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award options offering period.

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No definition available.

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- Definition

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

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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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No definition available.

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- Definition

Gross number of share options (or share units) granted during the period.

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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

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Equity-Based Compensation - Additional information (Detail)	1 Months Ended	9 Months Ended
	Feb. 28, 2017 Employee $ / shares shares	Sep. 29, 2018 shares	Sep. 30, 2017 USD ($)	Jan. 01, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase of common stock through payroll deductions		85.00%
Offering periods		2 years
Purchase intervals of a series		6 months
Maximum employee salary withholdings for purchase of common stock under the terms of the ESPP		15.00%
Cumulative effect of change in accumulated deficit \| $				$ 1,100,000
Number of shares issued under employee stock purchase plan		410,522
RSU conversion ratio		100.00%
Annual incentive plan stock awards granted		421,125
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of participants in restricted stock grants awarded \| Employee	33
Annual incentive plan stock awards granted	134,000
Weighted-average fair value of grants per share \| $ / shares	$ 9.63
Annual incentive plan equity-based compensation expense \| $			$ 102,000
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period		3 years
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award, vesting period		4 years