Increase in number of employee stock purchase plan shares authorized for issuance.

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Shares available for purchases under employee purchase plan.

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Shares purchased by employees under employee purchase plan.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

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Amount of noncash expense for share-based payment arrangement.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

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.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

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

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

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

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Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

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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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

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

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No definition available.

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Equity Plans and Stock-Based Compensation - Additional Information (Detail) - USD ($)				12 Months Ended
	May 30, 2019	May 31, 2018	May 28, 2014	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding stock awards granted				8,006,000	5,750,000
Total intrinsic value of options exercised				$ 26,000	$ 200,000	$ 900,000
Total fair value of stock options vested				19,500,000	8,100,000	13,000,000.0
Stock-based compensation expense				$ 25,456,000	23,478,000	14,917,000
Expected dividend yield				0.00%
Increase in aggregate number of shares of common stock authorized for issuance		600,000
Restructuring
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense				$ 4,122,000
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based compensation expense related to restricted stock				9,100,000
Aggregate intrinsic value				10,200,000
Total fair value of restricted stock units				$ 7,900,000	$ 19,400,000	1,200,000
Restricted stock unit awards outstanding				1,784,000	1,594,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding stock awards granted				155,000
Performance Based Vesting Condition
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock unit awards outstanding				89,000
Stock-based compensation expense				$ 500,000	$ 1,900,000	$ 300,000
Maximum \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period				10 years
Options vesting period				3 years
Minimum \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period				7 years
Options vesting period				4 years
2018 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Newly reserved shares of common stock		5,000,000
Shares remaining available for future purchases		140,250
Outstanding stock awards granted		7,477,619
Expiration period		7 years
Shares reserved and approved for issuance				3,308,216
2018 Equity Incentive Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares remaining available for future purchases		12,617,869
Amended 2018 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Newly reserved shares of common stock	2,300,000
Shares remaining available for future purchases	14,917,869
Time Based Vesting Schedule
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested equity awards				$ 28,000,000.0
Total unrecognized compensation cost, weighted-average vesting period				1 year 8 months 12 days
Performance Based Vesting Schedule
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested equity awards				$ 100,000
2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost related to non-vested equity awards				$ 400,000
Total unrecognized compensation cost, weighted-average vesting period				1 year 4 months 24 days
Shares issued to employees				122,117
Shares remaining available for future purchases				450,917
2014 Employee Stock Purchase Plan \| The commencement of the offer period (generally, the sixteenth day in February or August)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price per share as percentage of fair market value of common stock			85.00%
2014 Employee Stock Purchase Plan \| The exercise date, which is the last day of a purchase period (generally, the fifteenth day in February or August)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price per share as percentage of fair market value of common stock			85.00%