Debt (Tables)

9 Months Ended

Sep. 30, 2019

Debt consisted of the following (in millions):



	September 30, 2019		December 31, 2018
SHORT-TERM DEBT
Senior notes:
2.60% senior notes due December 2019	$	500	$	—
5.75% senior notes due January 2020	500		—
Other	84		66
Total short-term debt	1,084		66

LONG-TERM DEBT
Senior notes, net of unamortized discounts and debt issuance costs of $63 and $59, respectively ⁽¹⁾	8,937		8,941
GO Zone term loans, net of debt issuance costs of $1 and $2, respectively, bearing a weighted-average interest rate of 2.9% and 3.1%, respectively	199		198
Other	37		4
Total long-term debt	9,173		9,143
Total debt ⁽²⁾	$	10,257	$	9,209


⁽¹⁾	As of December 31, 2018, we classified our $500 million, 2.60% senior notes due December 2019 as long-term based on our ability and intent to refinance such amounts on a long-term basis.

⁽²⁾

Our fixed-rate senior notes had a face value of approximately $10.0 billion and $9.0 billion at September 30, 2019 and December 31, 2018, respectively. We estimated the aggregate fair value of these notes as of September 30, 2019 and December 31, 2018 to be approximately $10.3 billion and $8.6 billion, respectively. Our fixed-rate senior notes are traded among institutions, and these trades are routinely published by a reporting service. Our determination of fair value is based on reported trading activity near the end of the reporting period. We estimate that the carrying value of outstanding borrowings under our credit facilities, commercial paper program and GO Zone term loans approximates fair value as interest rates reflect current market rates. The fair value estimates for our senior notes, credit facilities, commercial paper program and GO Zone term loans are based upon observable market data and are classified in Level 2 of the fair value hierarchy.