Stockholders' Equity - Share-based Compensation Plans (Detail) shares in Millions	6 Months Ended
Jun. 30, 2020 plan	Jan. 01, 2020 shares
Share-based Compensation Arrangement by Share-based Payment Award
Share-based employee compensation plans, number \| plan	2
Equity Incentive Plan 2012
Share-based Compensation Arrangement by Share-based Payment Award
Equity incentive plan shares authorized (in shares) \| shares		171
Shares reserved for issuance increase, percentage	2.50%
Restricted Stock Units (RSUs) \| Equity Incentive Plan 2012
Share-based Compensation Arrangement by Share-based Payment Award
Vesting service period	4 years

Share-based Employee Compensation Plans, Number

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- Definition

Shares Reserved For Issuance Increase Percentage

+ References

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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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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.

+ 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 (a)(1)
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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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