Convertible Notes (Tables)

3 Months Ended

Mar. 31, 2019

Debt Disclosure [Abstract]

Schedule of convertible notes

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

(In thousands)	As of March 31, 2019			As of December 31, 2018
2023 Notes	$	172,500		$	172,500
Unamortized discount - 2023 Notes	(26,964		)	(28,517		)
Unamortized debt issuance costs - 2023 Notes	(1,924		)	(2,049		)
Total convertible notes	$	143,612		$	141,934
Less current portion	—			—
Total long-term convertible notes	$	143,612		$	141,934

Schedule of interest expense on notes

Interest expense related to the notes for the three months ended March 31, 2019 and 2018 was as follows:

	Three Months Ended
	March 31,
	2019		2018
	(In thousands)
2023 Notes coupon interest at a rate of 1.375%	$	593	$	593
2023 Notes amortization of discount and debt issuance costs at an additional effective interest rate of 4.9%	1,678		1,590
2018 Notes coupon interest at a rate of 1.125%	—		53
2018 Notes amortization of discount and debt issuance costs at an additional effective interest rate of 5.5%	—		1,090
Total interest expense on convertible notes	$	2,271	$	3,326