Performance stock unit award period.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options performance units granted percentage.

+ References

No definition available.

+ 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.

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- Definition

Number of non-option equity instruments exercised by participants.

+ References

+ Details

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- Definition

Number of shares under non-option equity instrument agreements that were either cancelled or expired.

+ References

+ Details

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ 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 (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

+ Details

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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

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- References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Stockholders' Equity (Deficit) - Summary of Activity for Outstanding Three-year PSU Awards (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
PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Outstanding at beginning of period (in shares)	629,504
Granted (in shares)	323,135
Converted (in shares)	(216,581)
Forfeited or expired (in shares)	(38,971)
Outstanding at end of period (in shares)	697,087	629,504
Fully vested at end of period (in shares)	209,631
Aggregate Intrinsic Value (in millions)
Converted	$ 9.8
Fully vested at end of period	$ 8.9
PSU Awards \| Minimum
Aggregate Intrinsic Value (in millions)
Performance units granted percentage	0.00%
PSU Awards \| Maximum
Aggregate Intrinsic Value (in millions)
Performance units granted percentage	200.00%