Debt (Tables)

3 Months Ended

Mar. 31, 2018

Debt Disclosure [Abstract]

Convertible Debt

The Convertible Notes consist of the following (in thousands):

	March 31, 2018			December 31, 2017
Liability component
Principal	$	1,437,483		$	1,437,483
Less: note discount and issuance costs	(41,436		)	(51,159		)
Net carrying amount	$	1,396,047		$	1,386,324
Equity component *	162,869			162,869

*Recorded in the condensed consolidated balance sheet within additional paid-in-capital.

Schedule of Interest Expense Recognized Related to Convertible Notes

The following table includes total interest expense recognized related to the Convertible Notes and the 2027 Notes (in thousands):

	Three Months Ended
	March 31,
	2018		2017
Contractual interest expense	$	10,235	$	1,797
Amortization of debt issuance costs	1,005		1,031
Amortization of debt discount	8,665		8,410
	$	19,905	$	11,238