Convertible Senior Notes ("Notes"), Note Hedges, and Warrants (Tables)

9 Months Ended

Sep. 30, 2017

Debt Disclosure [Abstract]

Schedule of Convertible Notes

The Notes consist of the following as of September 30, 2017, and December 31, 2016 (in thousands):

	September 30, 2017			December 31, 2016
Liability component	$	345,000		$	345,000
Debt discount, net of amortization		(26,488	)		(36,115	)
Debt issuance costs, net of amortization		(3,258	)		(4,401	)
Net carrying amount	$	315,255		$	304,484
Equity component	$	63,643		$	63,643
Less: debt issuance costs allocated to equity		(1,582	)		(1,582	)
Net carrying amount	$	62,061		$	62,061

Summary of Interest Expense Recognized Related to Notes

Interest expense recognized related to the Notes during the three and nine months ended September 30, 2017 and 2016 was as follows (in thousands):

	Three months ended September 30,				Nine months ended September 30,
	2017		2016		2017		2016
0.75% coupon	$	647	$	654	$	1,933	$	1,941
Amortization of debt issuance costs		388		373		1,144		1,092
Amortization of debt discount		3,265		3,126		9,627		9,152
	$	4,300	$	4,153	$	12,704	$	12,185