DEBT - Components of Interest Expense (Detail) (2016 Convertible Senior Notes, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
2016 Convertible Senior Notes
Debt Instrument [Line Items]
Amortization of the discount on the liability component	$ 1,859	$ 1,666
Cash interest related to the contractual interest coupon	845	801
Total	$ 2,704	$ 2,467

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.

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- Definition

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

+ References

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

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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.

+ References

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