DEBT (Tables)

12 Months Ended

Dec. 31, 2016

Senior Notes

Debt

Schedule of principal amount of the Senior Notes is repayable

The principal amount of the Senior Notes is repayable as follows (amounts in thousands):

April 2, 2018	$	57,500
April 2, 2019		115,000
April 2, 2020		115,000
April 2, 2021		143,750
April 2, 2022		43,750
	$	475,000

Summary of the carrying value of the Senior Notes

The following is a summary of the carrying value of the Senior Notes as of December 31, 2016 (in thousands):

	December 31,		December 31,
	2016		2015
Principal amount of the Senior Notes	$	475,000	$	575,000
Unamortized debt discount balance		(8,605)		(11,527)
Unamortized debt issuance costs		(344)		(461)
	$	466,051	$	563,012

Summary of interest expense for the Notes

The following is a summary of interest expense for 2016 and 2015 (in thousands):

	December 31,
	2016		2015
Contractual interest expense	$	54,722	$	46,874
Amortization of debt discount and debt issuance costs		2,261		1,466
Total interest expense	$	56,983	$	48,340

Convertible Notes

Debt

Summary of the liability component of the Convertible Notes

The following is a summary of the liability component of the Convertible Notes as of December 31, 2016 and 2015 (in thousands):

	December 31,		December 31,
	2016		2015
Principal amount of the Convertible Notes	$	345,000	$	345,000
Unamortized discount of the liability component		(87,570)		(101,965)
Unamortized debt issuance costs		(4,705)		(5,722)
	$	252,725	$	237,313

Summary of interest expense for the Notes

The following is a summary of interest expense for, 2016, 2015 and 2014 (in thousands):

	December 31,
	2016		2015		2014
Stated coupon interest	$	8,625		8,625		2,683
Amortization of debt discount and debt issuance costs		15,412		14,163		4,200
Total interest expense	$	24,037	$	22,788	$	6,883