Performance-based stock options outstanding.

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- Definition

Share based compensation arrangement by share based payment award employee stock purchase plan offering term.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award number of purchase period.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award term.

+ References

No definition available.

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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
-Subparagraph (SX 210.5-02.29)
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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

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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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- 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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
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-Section 50
-Paragraph 2
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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.

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- Definition

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

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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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- 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.

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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

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

+ References

No definition available.

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Stock-Based Compensation - Additional Information (Detail) $ in Millions	1 Months Ended		6 Months Ended
	Jun. 30, 2020 shares	Jun. 30, 2019 shares	Jun. 30, 2020 USD ($) Period shares	Dec. 31, 2019 shares
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, option to be granted at percentage of fair value of common stock			85.00%
Employee Stock Purchase Plan, offering period			12 months
Number of purchase periods within each offering period \| Period			2
Increase in shares of common stock authorized for issuance	1,500,000
Aggregate number of shares of common stock reserved for future issuance	1,900,000		1,900,000
2008 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, option to be granted at percentage of fair value of common stock			100.00%
Increase in shares of common stock authorized for issuance	5,000,000.0	11,800,000
Aggregate number of shares of common stock reserved for future issuance	32,400,000		32,400,000
Stock-based compensation, award term			10 years
Performance-based stock options, outstanding	40,000		40,000
Outstanding options and other stock based awards	18,318,000		18,318,000	16,830,000
Number of shares available for future issuance	8,400,000		8,400,000
2008 Equity Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period			4 years
2008 Equity Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of unvested Restricted Stock Units	5,722,000		5,722,000	4,098,000
2008 Equity Incentive Plan \| Performance-based Stock or Cash Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Stock Purchase Plan, authorized shares for issuance	500,000		500,000
Stock option plan granted on cash award \| $			$ 1.0
2008 Equity Incentive Plan \| Minimum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period			3 years
2008 Equity Incentive Plan \| Maximum \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period			4 years