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Computation of Basic and Diluted Net (Loss) Income Per Common Share (Parenthetical) (Detail) shares in Millions | 12 Months Ended
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Dec. 31, 2017 $ / shares shares
Convertible Notes |
Net Income Loss Per Common Share |
Initial debt conversion price | $ / shares | $ 31.80
Shares that would be issued upon conversion | shares | 14.5
Convertible Notes Hedge Warrant |
Net Income Loss Per Common Share |
Initial debt conversion price | $ / shares | $ 39.91
Shares that would be issued upon conversion | shares | 14.5

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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 + Details
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- Details
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- Details
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