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Computation of Basic and Diluted Net Income Per Common Share (Parenthetical) (Detail) shares in Millions	12 Months Ended
	Dec. 31, 2015 $ / shares shares
Convertible Notes
Net Income Loss Per Common Share
Initial debt conversion price | $ / shares	$ 5.48
Shares that would be issued upon conversion | shares	34.7
Convertible Notes Hedge Warrant
Net Income Loss Per Common Share
Initial debt conversion price | $ / shares	$ 7.67
Shares that would be issued upon conversion | shares	34.7

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- Definition

Antidilution adjustments of convertible note hedges.

+ References

No definition available.

+ Details

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- Definition

Net Income (Loss) Per Common Share [Line Items]

+ References

No definition available.

+ Details

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- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Details

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