Convertible Senior Notes (Tables)

3 Months Ended

Mar. 31, 2015

Debt Disclosure [Abstract]

Carrying Value of 2018 Convertible Notes

The carrying value of the 2018 Convertible Notes as of March 31, 2015 is summarized as follows:

Principal amount	$	120,000
(Less): Unamortized debt discount (amortized through December 2018)	(22,432		)
March 31, 2015	$	97,568

Components of the Interest Expense Recognized

The following table sets forth the components of the “interest expense” recognized in the accompanying Condensed Consolidated Statements of Operations for the 2018 Convertible Notes for the three months ended March 31, 2015:

Contractual coupon interest expense	$	825
Amortization of debt issuance costs	162
Accretion of debt discount	1,270
Total	$	2,257
Effective interest rate	8.66		%