Percentage of shares underlying the option award vesting monthly after the first anniversary.

No definition available.

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- Definition

Percentage of shares vesting on first anniversary.

+ References

No definition available.

+ Details

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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.

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

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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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- 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
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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Stock-Based Awards - Inducement Stock Option Awards (Detail) - $ / shares			12 Months Ended
	Jul. 09, 2019	Jun. 20, 2017	Dec. 31, 2019	Jul. 29, 2019
Stock-Based Awards
Shares Issuable Under Options, Granted			3,985,025
Exercise price (in dollars per share)			$ 4.06
Non-statutory Stock Option \| Management
Stock-Based Awards
Shares Issuable Under Options, Granted	60,000	590,000
Exercise price (in dollars per share)	$ 5.13	$ 10.94
Vesting period	4 years	4 years
Percentage of shares underlying the option award vesting on first anniversary	25.00%	25.00%
Percentage of shares underlying the option award vesting monthly after the first anniversary	75.00%	75.00%
Number of shares of common stock authorized for issuance			446,000	500,000