Debt

Our obligations under debt arrangements consisted of the following:



	March 31, 2017						December 31, 2016
	Principal		Unamortized Discount and Debt Issuance Costs		Net Value		Principal		Unamortized Discount and Debt Issuance Costs		Net Value
Senior secured credit facility	$	1,210,000	$	—	$	1,210,000	$	1,278,200	$	—	$	1,278,200
6.000% senior unsecured notes due May 2023	400,000		6,491		393,509		400,000		6,758		393,242
5.750% senior unsecured notes due February 2021	350,000		3,908		346,092		350,000		4,163		345,837
5.625% senior unsecured notes due June 2024	350,000		6,389		343,611		350,000		6,614		343,386
6.750% senior unsecured notes due August 2022	750,000		18,500		731,500		750,000		19,296		730,704
Total long-term debt	$	3,060,000	$	35,288	$	3,024,712	$	3,128,200	$	36,831	$	3,091,369

As of March 31, 2017, we were in compliance with the financial covenants contained in our credit agreement and senior unsecured notes indentures.

Senior Secured Credit Facility

The key terms for rates under our $1.7 billion senior secured credit facility, which are dependent on our leverage ratio (as defined in the credit agreement), are as follows:

•The applicable margin varies from 1.50% to 2.75% on Eurodollar borrowings and from 0.50% to 1.75% on alternate base rate borrowings.

•Letter of credit fees range from 1.50% to 2.50%

•The commitment fee on the unused committed amount will range from 0.25% to 0.50%.

•The accordion feature is $300.0 million, giving us the ability to expand the size of the facility up to $2.0 billion for acquisitions or growth projects, subject to lender consent.

At March 31, 2017, we had $1.2 billion borrowed under our $1.7 billion credit facility, with $70.0 million of the borrowed amount designated as a loan under the inventory sublimit. Our credit agreement allows up to $100.0 million of the capacity to be used for letters of credit, of which $8.7 million was outstanding at March 31, 2017. Due to the revolving nature of loans under our credit facility, additional borrowings and periodic repayments and re-borrowings may be made until the maturity date. The total amount available for borrowings under our credit facility at March 31, 2017 was $481.3 million.