Note 6—Debt

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

	March 31,		December 31,
	2014		2013
SHORT-TERM DEBT
PAA commercial paper notes, bearing a weighted-average interest rate of 0.30% and 0.33%, respectively (1) (2)	$	876	$	1,109
Other	3		4
Total short-term debt	879		1,113

LONG-TERM DEBT
Senior notes, net of unamortized discounts of $14 and $15, respectively	$	6,711	$	6,710
PAA commercial paper notes, bearing a weighted-average interest rate of 0.30% (2)	102		—
Other	5		5
Total long-term debt	6,818		6,715
Total debt (1) (3)	$	7,697	$	7,828

(1) At March 31, 2014 and December 31, 2013, we classified $876 million and $1.1 billion, respectively, of borrowings under our commercial paper program as short-term. These borrowings are primarily designated as working capital borrowings, must be repaid within one year and are primarily for hedged NGL and crude oil inventory and NYMEX and ICE margin deposits.

(2) PAA commercial paper notes are backstopped by the PAA senior unsecured revolving credit facility and the PAA senior secured hedged inventory facility, which mature in August 2018 and August 2016, respectively; as such, any borrowings under the PAA commercial paper program reduce the available capacity under these facilities. Although our PAA commercial paper notes generally have maturities of less than one year, we classified $102 million of such notes as long-term based on our ability and intent to refinance them on a long-term basis.

(3) Our fixed-rate senior notes had a face value of approximately $6.7 billion at both March 31, 2014 and December 31, 2013. We estimated the aggregate fair value of these notes as of March 31, 2014 and December 31, 2013 to be approximately $7.3 billion and $7.2 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 quarter end. We estimate that the carrying value of outstanding borrowings under our credit facilities and agreements and commercial paper program approximates fair value as interest rates reflect current market rates. The fair value estimates for both our senior notes and credit facilities are based upon observable market data and are classified within Level 2 of the fair value hierarchy.

Borrowings and Repayments

Total borrowings under our credit agreements and the commercial paper program for the three months ended March 31, 2014 and 2013 were approximately $19.2 billion and $3.2 billion, respectively. Total repayments under our credit agreements and the commercial paper program were approximately $19.3 billion and $3.6 billion for the three months ended March 31, 2014 and 2013, respectively. The variance in total gross borrowings and repayments is impacted by various business and financial factors including, but not limited to, the timing, average term and method of general partnership borrowing activities.

Letters of Credit

In connection with our supply and logistics activities, we provide certain suppliers with irrevocable standby letters of credit to secure our obligation for the purchase of crude oil, NGL and natural gas. Additionally, we issue letters of credit to support insurance programs and construction activities. At March 31, 2014 and December 31, 2013, we had outstanding letters of credit of approximately $70 million and $41 million, respectively.

Senior Notes Issuance

In April 2014, we completed the issuance of $700 million, 4.70% senior notes due 2044 at a public offering price of 99.734%. Interest payments are due on June 15 and December 15 of each year, commencing on December 15, 2014. In anticipation of the issuance of these senior notes, we entered into $250 million notional principal amount of U.S. treasury locks in March and April 2014 to hedge the treasury rate portion of the interest rate on a portion of the notes. See Note 10 for additional disclosure.