10. Debt and Interest Expense

Long‑term debt at December 31 consisted of the following:

	2014		2013
	(In millions)
Fixed-rate public notes:
7.0% due 2014	$	—	$	250
1.3% due 2017		300		—
8.1% due 2019		999		998
3.5% due 2024		298		—
7.9% due 2029		696		695
7.3% due 2031		747		747
7.1% due 2033		598		598
6.0% due 2040		745		745
5.6% due 2041		1,242		1,242
Total fixed-rate public notes		5,625		5,275
Financing obligations associated with floating production system		331		296
Other fixed-rate notes, weighted average rate 12.9%		—		135
Project lease financing, weighted average rate 5.1%		—		60
Fair value adjustments - interest rate hedging		31		30
Other debt		—		2
Total debt		5,987		5,798
Less: Short-term debt and current maturities of long-term debt		68		378
Total long-term debt	$	5,919	$	5,420

At December 31, 2014, the Corporation had a $4 billion syndicated revolving credit facility that is unused and has a maturity date of April 2016. This facility can be used for borrowings and letters of credit. Borrowings on the facility bear interest at 1.25% above the London Interbank Offered Rate. A fee of 0.25% per annum is also payable on the amount of the facility. The interest rate and facility fee are subject to adjustment if the Corporation’s credit rating changes. In January 2015, the Corporation entered into a new five-year credit agreement that replaces the previous agreement. See Note 22, Subsequent Events.

In June 2014, the Corporation issued $600 million of unsecured, fixed-rate notes ($598 million net of discount) comprising $300 million with a coupon of 1.3% and scheduled to mature in June 2017 as well as $300 million with a coupon of 3.5% and scheduled to mature in July 2024. In 2014, the Corporation repaid $590 million of debt, including $250 million of unsecured, fixed-rate notes, $249 million for the payment of various lease obligations primarily to retire retail gasoline station leases and $74 million assumed in the acquisition of WilcoHess.

During 2013, the Corporation repaid a net amount of $2,348 million under available credit facilities, which consisted of $758 million from its syndicated revolving credit facility, $990 million from the Corporation’s short-term credit facilities and $600 million from its asset-backed credit facility. The Corporation recorded capital lease obligations totaling $98 million in conjunction with its commitment to acquire 50 existing Hess retail gasoline stations that were previously held under operating leases. The Corporation repaid $136 million of other debt in 2013.

The Corporation recorded a non-cash net increase in debt of $68 million in 2014 and $116 million in 2013 related to progress on construction of a floating production system for the Tubular Bells Field, which commenced production in the fourth quarter of 2014.

At December 31, 2014, the Corporation’s fixed rate public notes have a principal amount of $5,650 million ($5,625 million net of unamortized discount). Interest rates on the outstanding fixed rate public notes have a weighted average rate of 6.4%.

The aggregate long‑term debt maturing during the next five years is as follows (in millions): 2015—$68; 2016—$71; 2017—$373; 2018—$78 and 2019—$1,070.

The Corporation’s long‑term debt agreements, including the revolving credit facility, contain financial covenants that restrict the amount of total borrowings and secured debt. The most restrictive of these covenants allow the Corporation to borrow up to an additional $5.6 billion of secured debt at December 31, 2014.

Outstanding letters of credit at December 31 were as follows:

	2014		2013
	(In millions)
Committed lines*	$	25	$	274
Uncommitted lines*		372		136
Total	$	397	$	410

*	Committed and uncommitted lines have expiration dates through 2016.

Of the $397 million of letters of credit outstanding at December 31, 2014, $54 million relates to contingent liabilities and the remaining $343 million relates to liabilities recorded in the Consolidated Balance Sheet.

The total amount of interest paid (net of amounts capitalized) was $326 million, $408 million and $419 million in 2014, 2013 and 2012, respectively. The Corporation capitalized interest of $76 million, $60 million and $28 million in 2014, 2013 and 2012, respectively.