Debt consisted of the following as of the dates indicated (in millions):


	September 30,		December 31,
	2015		2014
SHORT-TERM DEBT
Commercial paper notes, bearing a weighted-average interest rate of 0.43% and 0.46%, respectively (1)	$	678	$	734
Senior notes:
5.25% senior notes due June 2015		—		150
3.95% senior notes due September 2015		—		400
Other		3		3
Total short-term debt		681		1,287

LONG-TERM DEBT
Senior notes, net of unamortized discount of $18 and $18, respectively (2)		9,757		8,757
Commercial paper notes, bearing a weighted-average interest rate of 0.43% (2)		208		—
Other		5		5
Total long-term debt		9,970		8,762
Total debt (3)	$	10,651	$	10,049

⁽¹⁾

We classified these commercial paper notes as short-term at September 30, 2015 and December 31, 2014 as these notes were primarily designated as working capital borrowings, were required to be repaid within one year and were primarily for hedged NGL and crude oil inventory and NYMEX and ICE margin deposits.

⁽²⁾

As of September 30, 2015, we have classified our $175 million, 5.88% senior notes due August 2016 and a portion of our commercial paper notes as long-term based on our ability and intent to refinance such amounts on a long-term basis.

⁽³⁾

Our fixed-rate senior notes (including current maturities) had a face value of approximately $9.8 billion and $9.3 billion as of September 30, 2015 and December 31, 2014, respectively. We estimated the aggregate fair value of these notes as of September 30, 2015 and December 31, 2014 to be approximately $9.7 billion and $9.9 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 and commercial paper program approximates fair value as interest rates reflect current market rates. The fair value estimates for our senior notes, credit facilities and commercial paper program are based upon observable market data and are classified in Level 2 of the fair value hierarchy.