NOTE 3 DEBT

At September 30, 2015 and 2014, we had $500 million and $40 million, respectively, in unsecured long-term debt outstanding at rates and maturities shown in the following table:

	Principal				Unamortized Discount and Debt Issuance Costs
	September 30, 2015		September 30, 2014		September 30, 2015			September 30, 2014
	(in thousands)
Unsecured senior notes issued July 21, 2009:
Due July 21, 2015	$	—	$	40,000	$	—		$	(141	)
Due July 21, 2016		40,000		40,000		(498	)		(141	)
Unsecured revolving credit facility issued May 25, 2012		—		—		—			(581	)
Unsecured senior notes issued March 19, 2015:
Due March 19, 2025		500,000		—		(7,965	)		—

		540,000		80,000		(8,463	)		(863	)
Less long-term debt due within one year		40,000		40,000		(906	)		(365	)

Long-term debt	$	500,000	$	40,000	$	(7,557	)	$	(498	)

We have $40 million senior unsecured fixed-rate notes outstanding at September 30, 2015 that mature July 2016. Interest on the notes is paid semi-annually based on an annual rate of 6.10 percent. A final annual principal repayment of $40 million is due July 2016. We have complied with our financial covenants which require us to maintain a funded leverage ratio of less than 55 percent and an interest coverage ratio (as defined) of not less than 2.50 to 1.00.

On March 19, 2015, we issued $500 million of 4.65 percent 10-year unsecured senior notes. The net proceeds, after discount and issuance cost, will be used for general corporate purposes, including capital expenditures associated with our rig construction program. Interest is payable semi-annually on March 15 and September 15 each year, commencing on September 15, 2015. The debt discount is being amortized to interest expense using the effective interest method. The debt issuance costs are amortized straight-line over the stated life of the obligation, which approximates the effective yield method.

We have a $300 million unsecured revolving credit facility that will mature May 25, 2017. The credit facility has $100 million available to use for letters of credit. The majority of borrowings under the facility would accrue interest at a spread over the London Interbank Offered Rate (LIBOR). We also pay a commitment fee based on the unused balance of the facility. Borrowing spreads as well as commitment fees are determined according to a scale based on a ratio of our total debt to total capitalization. The spread over LIBOR ranges from 1.125 percent to 1.75 percent per annum and commitment fees range from .15 percent to .35 percent per annum. Based on our debt to total capitalization on September 30, 2015, the spread over LIBOR and commitment fees would be 1.125 percent and .15 percent, respectively. Financial covenants in the facility require us to maintain a funded leverage ratio (as defined) of less than 50 percent and an interest coverage ratio (as defined) of not less than 3.00 to 1.00. The credit facility contains additional terms, conditions, restrictions, and covenants that we believe are usual and customary in unsecured debt arrangements for companies of similar size and credit quality. As of September 30, 2015, there were no borrowings, but there were three letters of credit outstanding in the amount of $48.2 million. At September 30, 2015, we had $251.8 million available to borrow under our $300 million unsecured credit facility. Subsequent to September 30, 2015, we reduced our outstanding letters of credit by $7.9 million, which increased available borrowing capacity to $259.7.

At September 30, 2015, we had two letters of credit outstanding, totaling $12 million that were issued to support international operations. These letters of credit were issued separately from the $300 million credit facility so they do not reduce the available borrowing capacity discussed in the previous paragraph.

The applicable agreements for all unsecured debt contain additional terms, conditions and restrictions that we believe are usual and customary in unsecured debt arrangements for companies that are similar in size and credit quality. At September 30, 2015, we were in compliance with all debt covenants.

At September 30, 2015, aggregate maturities of long-term debt are as follows (in thousands):

Years ending September 30,
2016	$	40,000
2017		—
2018		—
2019		—
2020		—
Thereafter	$	500,000

	$	540,000