Convertible Senior Notes (Tables)

9 Months Ended

Sep. 30, 2015

Debt Disclosure [Abstract]

Schedule of the Liability and Equity Components of the Convertible Senior Notes

As of September 30, 2015, the liability and equity components of the Convertible Senior Notes consisted of the following (in thousands):

	Series A Notes			Series B Notes
Liability component:
Principal	$	460,000		$	460,000
Less: Convertible senior notes discounts and issuance costs, net of amortization	(98,151		)	(124,323		)
Net carrying amount	$	361,849		$	335,677
Equity component, net of issuance costs	$	92,567		$	117,834

Schedule of Interest Expense related to the Convertible Senior Notes

Interest expense related to the Convertible Senior Notes consisted of the following (in thousands):

	Three Months Ended September 30, 2015						Nine Months Ended September 30, 2015
	Series A Notes			Series B Notes			Series A Notes			Series B Notes
Coupon interest	$	1,150		$	1,869		$	1,533		$	2,492
Amortization of convertible senior notes discounts and issuance costs	4,623			3,942			6,150			5,247
Total interest expense recognized	$	5,773		$	5,811		$	7,683		$	7,739
Effective interest rate on the liability component	6.5		%	7.0		%	6.5		%	7.0		%