Information about Stock Options Outstanding (Parenthetical) (Detail) - Exercise Price Range, $ 2.00 - $ 2.46 $ in Millions	Dec. 31, 2015 USD ($)
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Aggregate intrinsic value, total options outstanding	$ 1
Aggregate intrinsic value, exercisable options	$ 1

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&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.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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