Shares available for purchases under employee purchase plan.

No definition available.

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- Definition

Shares purchased by employees under employee purchase plan.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

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

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

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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.

+ References

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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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.

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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

+ References

No definition available.

+ Details

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Equity Plans and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands			1 Months Ended	9 Months Ended
	May 30, 2019	May 28, 2014	May 31, 2018	Sep. 30, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in aggregate number of shares of common stock authorized for issuance			600,000
Outstanding stock awards granted				7,997,000	5,750,000
Restructuring
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense				$ 4,122
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value				$ 7,400
Restricted stock unit awards outstanding				2,068,000	1,594,000
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding stock awards granted				155,000
Employee Stock Option \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period				3 years
Expiration period				7 years
Employee Stock Option \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period				4 years
Expiration period				10 years
Performance Based Vesting Condition
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock unit awards outstanding				111,000
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
Shares reserved and approved for issuance				12,617,869
2011 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares remaining available for future purchases			7,477,619
Amended 2018 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase in aggregate number of shares of common stock authorized for issuance	2,300,000
Shares reserved and approved for issuance	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				$ 30,500
Total unrecognized compensation cost, weighted-average vesting period				1 year 7 months 6 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				$ 400
2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
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%