Convertible Notes Convertible Notes (Interest Expense for February 2018 Notes) (Detail) (Details) (February 2018 Notes [Member], USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014
February 2018 Notes [Member]
Debt Instrument [Line Items]
Contractual coupon interest	$ 1,571
Amortization of debt issuance costs	222
Amortization of debt discount	671
Total	$ 2,464

-- None. No documentation exists for this element. --

No definition available.

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- Definition

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.

+ References

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

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- Definition

Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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