Notes Payable (Tables)

12 Months Ended

Dec. 31, 2019

Long-term Debt, Unclassified [Abstract]

Schedule of net carrying amount of the liability and equity components of the Notes

The net carrying amount of the liability component of the Notes was as follows:

	As of December 31,
	2019			2018
	(In thousands)
Principal	$	549,999		$	550,000
Unamortized discount	(84,647		)	(106,484		)
Unamortized issuance costs	(7,162		)	(9,020		)
Net carrying amount	$	458,190		$	434,496

The net carrying amount of the equity component of the Notes was as follows:

	As of December 31,
	2019			2018
	(In thousands)
Proceeds allocated to the conversion options (debt discount)	$	119,435		$	119,435
Issuance costs	(2,819		)	(2,819		)
Net carrying amount	$	116,616		$	116,616

Schedule of interest expense recognized related to the Notes

The following table sets forth the interest expense recognized related to the Notes:

	Year Ended December 31,
	2019		2018
	(In thousands)
Contractual interest expense	$	1,375	$	852
Amortization of debt issuance costs	1,858		1,102
Amortization of debt discount	21,838		12,951
Total interest expense related to the Notes	$	25,071	$	14,905