LONG-TERM DEBT

Long-term debt obligations (in millions):



	2018			2017
Fixed-rate notes payable due through 2028	$	642		$	959
Variable-rate notes payable due through 2028	1,473			1,625
Less debt issuance costs	(12		)	(15		)
Total debt	2,103			2,569
Less current portion	486			307
Long-term debt, less current portion	$	1,617		$	2,262

Weighted-average fixed-interest rate	4.1		%	4.2		%
Weighted-average variable-interest rate	3.9		%	2.8		%

During 2018, the Company's total debt decreased $466 million, primarily due to payments of $807 million in 2018, including the prepayment of $451 million of debt. These reductions in debt were offset by the addition of secured debt financing from multiple lenders of $339 million. All outstanding debt is secured by aircraft, spare engines or by interest in certain aircraft purchase deposits.

The Company's variable-rate debt bears interest at a floating rate per annum equal to a margin plus the three or six-month LIBOR in effect at the commencement of each three or six-month period, as applicable. As of December 31, 2018, none of the Company's borrowings were restricted by financial covenants.

Long-term debt principal payments for the next five years and thereafter (in millions):



	Total
2019	$	488
2020	305
2021	263
2022	216
2023	262
Thereafter	579
Total principal payments	$	2,113

Subsequent to year end, the Company prepaid approximately $262 million of outstanding secured debt. This debt is classified as short-term in nature on our Consolidated Balance Sheet as of December 31, 2018. Also subsequent to year end, the Company obtained additional secured debt financing of $254 million from multiple lenders. The new debt is secured by a total of nine aircraft.

Bank Line of Credit

The Company has three credit facilities with availability totaling $516 million. All three facilities have variable interest rates based on LIBOR plus a specified margin. One credit facility for $250 million expires in June 2021 and is secured by aircraft. A second credit facility increased from $75 million to $116 million in July 2018. It expires in July 2019, with a mechanism for annual renewal, and is secured by aircraft. A third credit facility for $150 million expires in March 2022 and is secured by certain accounts receivable, spare engines, spare parts and ground service equipment. The Company has secured letters of credit against the $116 million facility, but has no plans to borrow using either of the two other facilities. All three credit facilities have a requirement to maintain a minimum unrestricted cash and marketable securities balance of $500 million. The Company was in compliance with this covenant at December 31, 2018.