Performance stock unit award period.

No definition available.

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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
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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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

+ Details

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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.

+ Details

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- Details

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Stockholders' Equity (Deficit) - Summary of Unrecognized Compensation Cost for Three-year PSU Awards and Weighted Average Period (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Three-year PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PSU awards performance period	3 years	3 years	3 years
2020 Three-year PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 5.9
Weighted Average to be recognized (in years)	2 years
2019 Three-year PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 3.0
Weighted Average to be recognized (in years)	1 year
2018 Three-year PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Costs	$ 0.0
Weighted Average to be recognized (in years)	0 years