Interest Expense Recognized Related To Notes (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013
Schedule Of Interest Expenses [Line Items]
Accretion of convertible note discount	$ 4,846
Convertible Senior Notes
Schedule Of Interest Expenses [Line Items]
Accretion of convertible note discount	$ 4,846

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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