Convertible Senior Notes (Tables)

9 Months Ended

Sep. 30, 2020

Summary of Net Carrying Amount of Liability and Equity Component of 2025 Notes

The net carrying amount of the liability component of the 2025 Notes was as follows (in thousands):

	September 30, 2020
Principal	$	747,500
Unamortized debt discount		(167,240	)
Unamortized debt issuance costs		(12,577	)
Net carrying amount	$	567,683

The net carrying amount of the equity component of the 2025 Notes was as follows (in thousands):

	September 30, 2020
Debt discount for conversion option	$	177,169
Issuance costs		(4,099	)
Net carrying amount	$	173,070

Interest Expense related to 2025 Notes

The following table sets forth the interest expense related to the 2025 Notes for each of the three and nine months ended September 30, 2020 (in thousands):

	Three Months Ended September 30,		Nine Months Ended September 30,
	2020		2020
Contractual interest expense	$	234	$	306
Amortization of debt discount		7,589		9,929
Amortization of issuance costs		473		617
Total	$	8,296	$	10,852