Debt Arrangements (Tables)

6 Months Ended

Jun. 30, 2015

Net Carrying Amount of Debt

The Company’s net carrying amount of debt is comprised of the following:

	June 30, 2015		December 31, 2014
Senior Secured Notes	$	743,469	$	774,030
1.50% Convertible Notes		348,321		339,943
2.50% Convertible Notes		286,795		280,104
Variable Funding Note		100,000		—
Total	$	1,478,585	$	1,394,077

Company's Debt Maturities on Calendar Year Basis

As of June 30, 2015, the Company’s debt maturities on a calendar year basis are as follows:

	Total		July 1 through December31, 2015		2016		2017		2018		2019		Thereafter
Senior Secured Notes	$	743,469	$	30,562	$	61,123	$	61,123	$	61,123	$	61,123	$	468,415
1.50% Convertible Notes (1)	$	348,321		—		—		—		348,321				—
2.50% Convertible Notes  (2)	$	286,795		—		286,795		—		—		—		—
Variable Funding Notes	$	100,000								100,000
Total	$	1,478,585	$	30,562	$	347,918	$	61,123	$	509,444	$	61,123	$	468,415

(1) Reflects the net debt carrying amount of the 1.50% Convertible Notes in the consolidated balance sheet as of June 30, 2015, in accordance with accounting for convertible notes. The principal amount owed to the holders of the 1.50% Convertible Notes is $400.0 million.

(2) Reflects the net debt carrying amount of the 2.50% Convertible Notes in the consolidated balance sheet as of June 30, 2015, in accordance with accounting for convertible notes. The principal amount owed to the holders of the 2.50% Convertible Notes is $300.0 million.

Convertible Notes | 1.50% Senior Subordinated Notes Due March 15, 2018

Details of Convertible Notes Reflected on Consolidated Balance Sheet

As of June 30, 2015 and December 31, 2014, the amount of the 1.50% Convertible Notes accounted for as a liability was approximately $348.3 million and $339.9 million, respectively, and is reflected on the unaudited condensed consolidated balance sheets as follows:

	June 30, 2015		December 31, 2014
Equity component carrying amount	$	49,931	$	49,931
Unamortized discount		51,679		60,057
Net debt carrying amount		348,321		339,943

Convertible Notes | 2.50% Senior Subordinated Notes Due June 2016

Details of Convertible Notes Reflected on Consolidated Balance Sheet

As of June 30, 2015 and December 31, 2014, the amount of the 2.50% Convertible Notes accounted for as a liability was approximately $286.8 million (which is included in current portion of long-term debt) and $280.1 million, respectively, and is reflected on the condensed consolidated balance sheets as follows:

	June 30, 2015		December 31, 2014
Equity component carrying amount	$	35,996	$	35,996
Unamortized discount		13,205		19,896
Net debt carrying amount		286,795		280,104