CREDIT FACILITY AND LONG-TERM DEBT CREDIT FACILITY AND LONG-TERM DEBT (Tables)

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Convertible Debt

The following table summarizes the net carrying amount of the Notes as of December 31, 2021 (in thousands):

	December 31, 2021		December 31, 2020
Principal amount of the Notes	$	86,250	$	86,250
Unamortized debt discount	(2,216)		(37,791)
Net carrying amount	$	84,034	$	48,459

Interest Income and Interest Expense Disclosure

Interest expense related to the Notes is comprised of the amortization of debt discount and debt issuance costs and the contractual coupon interest as follows (in thousands):

	Year Ended December 31,
	2021		2020		2019
Interest expense related to contractual coupon interest2	$	3,755	$	3,234	$	925
Interest expense related to amortization of debt discount1	415		3,111		1,744
Total interest expense	$	4,170	$	6,345	$	2,669

1 Refer to Note 1. Summary of Significant Accounting Policies relating to an immaterial out of period error correction of non-cash interest identified and recorded during the fourth fiscal quarter of 2020.

2The year ended December 31, 2021 includes $0.5 million of additional interest expense related to the restrictive legend on the Notes. The legend was removed as of December 31, 2021 and the Notes will not accrue additional interest in future periods.