Convertible Notes

6 Months Ended

Jun. 30, 2019

Debt Disclosure [Abstract]

Convertible Notes

Convertible Notes

The Company’s convertible notes are shown in the following table:

(In thousands)	As of June 30, 2019			As of December 31, 2018
2023 Notes	$	172,500		$	172,500
Unamortized discount - 2023 Notes	(25,386		)	(28,517		)
Unamortized debt issuance costs - 2023 Notes	(1,800		)	(2,049		)
Total convertible notes	$	145,314		$	141,934
Less current portion	—			—
Total long-term convertible notes	$	145,314		$	141,934

Interest expense related to the notes for the three and six months ended June 30, 2019 and 2018 was as follows:

	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2019		2018		2019		2018
	(In thousands)
2023 Notes coupon interest at a rate of 1.375%	$	593	$	593	$	1,186	$	1,186
2023 Notes amortization of discount and debt issuance costs at an additional effective interest rate of 4.9%	1,701		1,610		3,379		3,199
2018 Notes coupon interest at a rate of 1.125%	—		228		—		281
2018 Notes amortization of discount and debt issuance costs at an additional effective interest rate of 5.5%	—		1,106		—		2,197
Total interest expense on convertible notes	$	2,294	$	3,537	$	4,565	$	6,863