Debt (Tables)

3 Months Ended

Mar. 31, 2015

Debt Disclosure [Abstract]

Summary of Convertible Notes and Equity Component

The Convertible Notes and the equity component, which is recorded in additional paid-in-capital, consisted of the following:

	March 31, 2015			December 31, 2014
	(in thousands)
Principal amount	$	143,750		$	143,750
Unamortized discount		(26,879	)		(28,947	)
Net carrying amount	$	116,871		$	114,803
Equity component	$	55,038		$	55,038

Summary of Interest Expense Related to Convertible Notes

For the three months ended March 31, 2015 and 2014, interest expense related to the Convertible Notes was as follows:

	Three Months Ended March 31
	2015		2014
	(in thousands)
Stated amount at 3.5% coupon rate	$	1,258	$	1,258
Amortization of discount		2,068		1,834
Amortization of deferred financing costs		111		99
	$	3,437	$	3,191