Debt The Company's outstanding debt is senior unsecured, except for borrowings, if any, under the $5.0 billion Facility. See Note 11—Equity-Method Investments for disclosure regarding Anadarko's notes payable related to its ownership of certain noncontrolling mandatorily redeemable interests that are not included in the Company's reported debt balance and do not affect consolidated interest expense. The following summarizes the Company's outstanding debt:


	December 31,
millions	2012		2011
6.125% Senior Notes due 2012	$	—	$	131
5.000% Senior Notes due 2012		—		39
5.750% Senior Notes due 2014		275		275
7.625% Senior Notes due 2014		500		500
5.950% Senior Notes due 2016		1,750		1,750
6.375% Senior Notes due 2017		2,000		2,000
7.050% Debentures due 2018		114		114
6.950% Senior Notes due 2019		300		300
8.700% Senior Notes due 2019		600		600
WES 5.375% Senior Notes due 2021		500		500
WES 4.000% Senior Notes due 2022		670		—
6.950% Senior Notes due 2024		650		650
7.500% Debentures due 2026		112		112
7.000% Debentures due 2027		54		54
7.125% Debentures due 2027		150		150
6.625% Debentures due 2028		17		17
7.150% Debentures due 2028		235		235
7.200% Debentures due 2029		135		135
7.950% Debentures due 2029		117		117
7.500% Senior Notes due 2031		900		900
7.875% Senior Notes due 2031		500		500
Zero-Coupon Senior Notes due 2036		2,360		2,360
6.450% Senior Notes due 2036		1,750		1,750
7.950% Senior Notes due 2039		325		325
6.200% Senior Notes due 2040		750		750
7.730% Debentures due 2096		61		61
7.500% Debentures due 2096		78		78
7.250% Debentures due 2096		49		49
$5.0 billion Facility		—		2,500
Total debt at face value	$	14,952	$	16,952
Net unamortized discounts and premiums⁽¹⁾		(1,683)		(1,722)
Total borrowings	$	13,269	$	15,230
Less current portion of long-term debt		—		170
Total long-term debt	$	13,269	$	15,060

(1) Unamortized discounts and premiums are amortized over the term of the related debt.

In a 2006 private offering, Anadarko received $500 million of loan proceeds upon issuing the Zero-Coupon Senior Notes due 2036 (Zero Coupons). The Zero Coupons mature in 2036 and have an aggregate principal amount due at maturity of $2.4 billion, reflecting a yield to maturity of 5.24%. The holder has the right to cause the Company to repay an amount up to the then-accreted value of the outstanding Zero Coupons in October of each year. The holder did not elect to put any of the accreted balance of the Zero Coupons to the Company in October 2012. The Zero Coupons are classified as long-term debt on the Consolidated Balance Sheets based on the Company's ability and intent to refinance the obligations, if the holder requests repayment in 2013.

Fair Value The Company uses a market approach to determine fair value of its fixed-rate debt using observable market data, which results in a Level 2 fair-value measurement. The carrying amount of floating-rate debt approximates fair value as the interest rates are variable and reflective of market rates. The estimated fair value of the Company's total borrowings was $16.2 billion at December 31, 2012, and $17.3 billion at December 31, 2011.

Debt Activity The following summarizes the Company's debt activity during 2012 and 2011:


		Carrying
millions		Value		Description
Balance at December 31, 2010		$	12,787
	Issuances		494	WES 5.375% Senior Notes due 2021
	Borrowings		570	WES revolving credit facility
			2,500	$5.0 billion Facility
	Repayments		(869)	WES revolving credit facility and WES term loan
			(285)	6.875% Senior Notes due 2011
	Other, net		33	Changes in debt premium or discount
Balance at December 31, 2011		$	15,230
	Issuances		674	WES 4.000% Senior Notes due 2022
	Borrowings		374	WES revolving credit facility
	Repayments		(131)	6.125% Senior Notes due 2012
			(39)	5.000% Senior Notes due 2012
			(374)	WES revolving credit facility
			(2,500)	$5.0 billion Facility
	Other, net		35	Changes in debt premium or discount
Balance at December 31, 2012		$	13,269

Capital Lease Obligation In the fourth quarter of 2010, a lease commenced for a floating production, storage, and offloading vessel (FPSO) for the Company's Jubilee field operations in Ghana. In December 2011, the Company and its partners in the Jubilee project purchased the FPSO, resulting in the cancellation of the capital lease obligation.

Anadarko Revolving Credit Facility and Letter of Credit Facility In September 2010, the Company entered into the $5.0 billion Facility maturing in September 2015. Borrowings under the $5.0 billion Facility bear interest at LIBOR plus an applicable margin ranging from 1.25% to 2.50%, depending on the Company's credit rating, or rates at a margin above the one-month LIBOR, the federal funds rate, or prime rates offered by certain designated banks. During 2012, the Company repaid all outstanding borrowings under the $5.0 billion Facility with cash on hand and cash realized from the resolution of the Algeria exceptional profits tax dispute.

Obligations incurred under the $5.0 billion Facility, as well as obligations Anadarko has to lenders or their affiliates pursuant to certain derivative instruments that are supported by the $5.0 billion Facility (as discussed in Note 12—Derivative Instruments), are guaranteed by certain of the Company's wholly owned domestic subsidiaries, and are secured by a perfected first-priority security interest in certain exploration and production assets located in the United States and 65% of the capital stock of certain wholly owned foreign subsidiaries. At December 31, 2012, the Company was in compliance with applicable covenants and there were no restrictions on its ability to utilize the $5.0 billion Facility.

In 2011, the Company entered into an agreement with a financial institution to provide up to $400 million of letters of credit (LOC Facility). In the third quarter of 2012, the Company terminated the LOC Facility.

WES Borrowings In March 2011, WES entered into a five-year, $800 million senior unsecured revolving credit facility (RCF). The $800 million RCF matures in March 2016 and bears interest at LIBOR plus an applicable margin ranging from 1.30% to 1.90%, or rates at a margin above the one-month LIBOR, the federal funds rate, or prime rates offered by certain designated banks. In 2012, WES repaid all outstanding borrowings under its RCF with net proceeds from its public offering of $670 million aggregate principal amount of 4.000% Senior Notes due 2022. At December 31, 2012, WES was in compliance with all of the covenants contained in the RCF.

Scheduled Maturities Total principal amount of debt maturities for the five years ending December 31, 2017, excluding the potential repayment of the outstanding Zero Coupons that may be put by the holder to the Company annually, were as follows:

Interest Expense The following summarizes interest expense for the years ended December 31:

(1) Loss on early debt retirements in 2010 is the result of repurchasing $1.4 billion aggregate principal amount of debt due 2011 and 2012.