Convertible Senior Notes (Tables)

12 Months Ended

Dec. 31, 2016

Debt Disclosure [Abstract]

Schedule of Debt

The 2017 Notes consisted of the following:

Liability component	December 31, 2016			December 31, 2015
	(In thousands)
Principal	$	55,000		$	275,000
Less: Debt discount, net(1)	(1,251		)	(19,527		)
Net carrying amount	$	53,749		$	255,473

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(1) Included on the accompanying consolidated balance sheets within convertible senior notes (due 2017) and amortized to interest expense over the remaining life of the 2017 Notes using the effective interest rate method.

The 2023 Notes consist of the following:

Liability component	December 31, 2016			December 31, 2015
	(in thousands)
Principal	$	402,500		$	—
Less: Debt discount, net(1)	(103,162		)	—
Net carrying amount	$	299,338		$	—

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⁽¹⁾  Included in the accompanying condensed consolidated balance sheets within convertible senior notes (due 2023) and amortized to interest expense over the remaining life of the 2023 Notes using the effective interest rate method.

The 2022 Notes consist of the following:

Liability component	December 31, 2016			December 31, 2015
	(In thousands)
Principal	$	400,000		$	400,000
Less: Debt discount, net(1)	(75,754		)	(87,893		)
Net carrying amount	$	324,246		$	312,107

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⁽¹⁾  Included on the accompanying consolidated balance sheets within convertible senior notes (due 2022) and amortized to interest expense over the remaining life of the 2022 Notes using the effective interest rate method.

Schedule of Interest Expense

The following table sets forth total interest expense recognized related to the 2022 Notes:

	Years Ended December 31,
	2016			2015			2014
	(In thousands)
Contractual interest expense	$	10,000		$	9,639		$	—
Amortization of debt discount	12,139			10,942			—
Total	$	22,139		$	20,581		$	—
Effective interest rate of the liability component	6.50		%	6.50		%	—		%

The following table sets forth total interest expense recognized related to the 2017 Notes:

	Years Ended December 31,
	2016			2015			2014
	(In thousands)
Contractual interest expense	$	2,101		$	3,781		$	3,781
Amortization of debt discount	7,395			12,734			11,920
Total	$	9,496		$	16,515		$	15,701
Effective interest rate of the liability component	6.02		%	6.02		%	6.02		%

The following table sets forth total interest expense recognized related to the 2023 Notes:

	Years Ended December 31,
	2016			2015			2014
				(in thousands)
Contractual interest expense	$	6,158		$	—		$	—
Amortization of debt discount	6,648			—			—
Total	$	12,806		$	—		$	—
Effective interest rate of the liability component	7.5		%	—		%	—		%