Long-term Debt

As of December 31, 2015, the Company had aggregate outstanding $2,371.4 million, net of $28.6 million of issuance costs, in long-term notes with varying maturities (the "Notes"). Each of the Notes were issued at par and are senior unsecured obligations of the Company. Interest is payable semi-annually at fixed rates.

The following table provides a summary of the Company's outstanding long-term debt and the fair values based on quoted market prices in less active markets as of December 31, 2015 and December 31, 2014:



						Level 2 Fair Value as of
	Principal Amount at Par		Issuance Date	Maturity	Interest Due Dates	December 31, 2015		December 31, 2014
	(in millions)					(in millions)
5.50% Senior Notes	$	700.0	February 2015	2022	April 15 and October 15	$	717.5	$	—
5.875% Senior Notes	800.0		February 2015	2025	April 15 and October 15	820.0		—
5.750% Senior Notes	400.0		February 2014	2024	March 1 and September 1	411.0		416.0
5.375% Senior Notes	500.0		February 2013	2021	February 1 and August 1	525.0		520.0

Each of the Notes are repayable in whole or in part upon the occurrence of a change of control, at the option of the holders, at a purchase price in cash equal to 101% of the principal plus accrued interest. The Company may redeem the Notes prior to maturity in whole or in part at an amount equal to the principal amount thereof plus accrued and unpaid interest and an applicable premium. The Notes include, among other terms and conditions, limitations on the Company's ability to create, incur or allow certain liens; enter into sale and lease-back transactions; create, assume, incur or guarantee additional indebtedness of certain of the Company's subsidiaries; and consolidate or merge with, or convey, transfer or lease all or substantially all of the Company's and its subsidiaries assets, to another person. As of December 31, 2015 and December 31, 2014, the Company was in compliance with all related covenants.

In November 2011, the Company issued $200.0 million aggregate principal amount of zero coupon senior convertible notes due on December 1, 2018 (the “Convertible Notes”) in a private placement offering to TCV VII, L.P., TCV VII(A), L.P., and TCV Member Fund, L.P. A general partner of these funds also serves on the Company’s Board of Directors, and as such, the issuance of the notes is considered a related party transaction. In April 2013, the Company elected to cause the conversion of all outstanding Convertible Notes in accordance with the terms of the Indenture governing such notes. Pursuant to this conversion, the Company issued 16.3 million shares of common stock to the holders of the Convertible Notes at a conversion ratio of 81.5871, as adjusted for the Stock Split. The fair market value of one share of common stock on the date of conversion was $31.00 per share, as adjusted for the Stock Split.

In November 2009, the Company issued $200.0 million aggregate principal amount of 8.50% senior notes due November 15, 2017 (the "8.50% Notes"). Interest was payable semi-annually at a rate of 8.50% per annum on May 15 and November 15 of each year. In the first quarter of 2013, the Company redeemed the outstanding $200.0 million aggregate principal amount of 8.50% Notes and pursuant to the make-whole provision in the Indenture governing the 8.50% Notes, paid a $19.4 million premium and $5.1 million of accrued and unpaid interest. The Company recognized a loss on extinguishment of debt of $25.1 million related to redemption of the 8.50% Notes which included the write off of unamortized debt issuance costs of $4.2 million.