	December 31,			December 31,
	2013			2012
SHORT-TERM DEBT
Credit Facilities (1):
PAA senior secured hedged inventory facility, bearing a weighted-average interest rate of 1.6% at December 31, 2012 (2)	$	—		$	665
PAA senior unsecured revolving credit facility, bearing a weighted-average interest rate of 2.4% at December 31, 2012 (2)	—			92
PNG senior unsecured revolving credit facility, bearing a weighted-average interest rate of 2.1% at December 31, 2012 (3)	—			77
PAA commercial paper notes, bearing a weighted-average interest rate of 0.33% at December 31, 2013 (2)	1,109			—
5.63% senior notes due December 2013	—			250
Other	4			2
Total short-term debt	1,113			1,086

LONG-TERM DEBT
Senior Notes:
5.25% senior notes due June 2015	150			150
3.95% senior notes due September 2015	400			400
5.88% senior notes due August 2016	175			175
6.13% senior notes due January 2017	400			400
6.50% senior notes due May 2018	600			600
8.75% senior notes due May 2019	350			350
5.75% senior notes due January 2020	500			500
5.00% senior notes due February 2021	600			600
3.65% senior notes due June 2022	750			750
2.85% senior notes due January 2023	400			400
3.85% senior notes due October 2023	700			—
6.70% senior notes due May 2036	250			250
6.65% senior notes due January 2037	600			600
5.15% senior notes due June 2042	500			500
4.30% senior notes due January 2043	350			350
Unamortized discounts	(15		)	(15		)
Senior notes, net of unamortized discounts	6,710			6,010
Credit Facilities and Other Long-Term Debt (1):
PNG senior unsecured revolving credit facility, bearing a weighted-average interest rate of 2.1% at December 31, 2012 (3)	—			105
PNG GO Bond term loans, bearing a weighted-average interest rate of 1.5% at December 31, 2012 (3)	—			200
Other	5			5
Total long-term debt	6,715			6,320
Total debt (2) (3) (4)	$	7,828		$	7,406

(1) During 2013 and 2012, we renewed, extended or refinanced our principal bank credit facilities. See “Credit Facilities” below for further discussion.

(2) We classify as short-term certain borrowings under our commercial paper program, PAA senior unsecured revolving credit facility and PAA senior secured hedged inventory facility. 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.

(3) On December 31, 2013, in connection with the completion of the PNG Merger, all of PNG’s outstanding debt obligations were repaid and terminated. See Note 10 for further discussion of the PNG Merger.

(4) Our fixed-rate senior notes (including current maturities) had a face value of approximately $6.7 billion and $6.3 billion as of December 31, 2013 and 2012, respectively. We estimated the aggregate fair value of these notes as of December 31, 2013 and 2012 to be approximately $7.2 billion and $7.3 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 year 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.