Convertible Senior Notes (Tables)

6 Months Ended

Jun. 30, 2016

Debt Disclosure [Abstract]

Schedule of long-term debt instruments

The Notes consisted of the following (in thousands):

	June 30, 2016			December 31, 2015
Liability:
Principal	$	1,322,500		$	1,322,500
Less: debt discount, net of amortization	(172,368		)	(195,966		)
Net carrying amount	$	1,150,132		$	1,126,534
Equity	$	230,191		$	230,191

Schedule of recognized interest expense

The Company recognized interest expense on the Notes as follows (in thousands, except for percentages):

	Three Months Ended June 30,						Six Months Ended June 30,
	2016			2015			2016			2015
Contractual interest expense based on 0.50% per annum	$	1,653		$	1,672		$	3,306		$	3,325
Amortization of debt discount and issuance costs	11,868			11,322			23,598			22,511
Total	$	13,521		$	12,994		$	26,904		$	25,836
Effective interest rate of the liability component	4.7		%	4.7		%	4.7		%	4.7		%