DEBT

A summary of long-term debt is as follows:



(In thousands)	March 31, 2015		September 30, 2014
6.5% Senior Notes due 2020 ("Senior Notes")	$	656,542	$	657,122
Revolving Credit Facility	950,000		1,085,000
Total long-term debt	$	1,606,542	$	1,742,122

Senior Notes

As of March 31, 2015, our Senior Notes had an aggregate principal amount of $650 million. Our Senior Notes are unsecured obligations and are not guaranteed by any of our subsidiaries. We received a premium of $8.5 million as part of the net proceeds for the Senior Notes issued. This premium is being amortized over the life of our Senior Notes.

Revolving Credit Facility

On March 5, 2015, we entered into an amendment to our senior secured credit facility (the "Credit Facility"), which, among other things, (i) extended the maturity with respect to $1.175 billion of the total $1.55 billion of commitments under the Credit Facility to May 2019 and (ii) amended the maximum leverage ratio upwards to 4.50:1.00 through December 31, 2017, after which period the maximum leverage ratio will revert back to 4.00:1.00 through maturity. The amendment also permits those lenders who did not extend the maturity to do so at a later date. In April 2015, an additional $70 million of commitments were extended. The remaining non-extended commitments of approximately $300 million mature in May 2018.

As of March 31, 2015, we had $950 million of outstanding borrowings and $6.7 million of letters of credit issued under the Credit Facility. As of March 31, 2015, we had approximately $593 million available for borrowings under the Credit Facility. Borrowings under the Credit Facility bear interest at the Eurodollar rate plus a margin ranging from 1.75% to 2.00% and the commitment fee on the unused portion of the underlying commitment ranges from 0.30% to 0.40% per annum, in each case based on our corporate credit ratings. Obligations under the Credit Facility are secured primarily by first preferred mortgages on nine of our drilling units as well as liens on the equity interests of our subsidiaries that own, directly or indirectly, such drilling units. Our Credit Facility contains various financial covenants. At March 31, 2015, we were in compliance with those covenants.

The weighted-average effective interest rate on our revolving Credit Facility was approximately 2.3% per annum at March 31, 2015. The effective rate was determined after giving consideration to the effect of our interest rate swaps accounted for as hedges and the amortization of premiums or discount. Interest capitalized for the three and six months ended March 31, 2015 was approximately $4 million and $9 million, respectively. Interest capitalized for the three and six months ended March 31, 2014 was approximately $6 million and $16 million, respectively.