Debt

The following table summarizes the carrying value of our outstanding debt:



	Coupon		Carrying Value as of		Effective		Carrying Value as of		Effective
	Rate		March 31, 2013		Interest Rate		December 31, 2012		Interest Rate
	(In millions, except percentages)
Long-Term Debt
Senior notes due 2015	1.625	%	$	599	1.805	%	$	599	1.805	%
Senior notes due 2015	0.700	%	250		0.820	%	250		0.820	%
Senior notes due 2017	1.350	%	999		1.456	%	999		1.456	%
Senior notes due 2020	3.250	%	498		3.389	%	498		3.389	%
Senior notes due 2022	2.600	%	999		2.678	%	999		2.678	%
Senior notes due 2042	4.000	%	743		4.114	%	742		4.114	%
Total senior notes			4,088				4,087
Notes payable			12				13
Capital lease obligations			5				6
Total long-term debt			$	4,105			$	4,106

Short-Term Debt
Senior notes due 2013	0.875	%	$	400	1.078	%	$	400	1.078	%
Notes payable			2				2
Capital lease obligations			9				11
Total short-term debt			411				413
Total Debt			$	4,516			$	4,519

Senior Notes

The effective interest rates for our fixed-rate senior notes include the interest payable, the amortization of debt issuance costs and the amortization of any original issue discount on these senior notes. Interest on these senior notes is payable semiannually. Interest expense associated with these senior notes, including amortization of debt issuance costs, during the three months ended March 31, 2013 and 2012 was approximately $26 million and $8 million, respectively. At March 31, 2013, the estimated fair value of all these senior notes included in long-term debt was approximately $4.1 billion based on market prices on less active markets (Level 2).

The indenture pursuant to which the senior notes were issued includes customary covenants that, among other things and subject to exceptions, limit our ability to incur, assume or guarantee debt secured by liens on specified assets or enter into sale and lease-back transactions with respect to specified properties, and also includes customary events of default.

Notes Payable

Notes payable is comprised primarily of a note that bears interest at 6.3% per annum and has a maturity date of July 2034. We have an accelerated prepayment option exercisable in July 2014.

Capital Lease Obligations

Capital lease obligations are for certain warehouse equipment and computer hardware and software leases. The capital leases have maturity dates ranging from May 2013 to September 2014 and bear interest at rates ranging from 3% to 9% per annum. The present value of future minimum capital lease payments as of March 31, 2013 was as follows (in millions):



	March 31, 2013
	(In millions)
Gross capital lease obligations	$	15
Imputed interest	(1		)
Total present value of future minimum capital lease payments	$	14

Commercial Paper

We have a $2 billion commercial paper program pursuant to which we may issue commercial paper notes with maturities of up to 397 days from the date of issue. As of March 31, 2013, there were no commercial paper notes outstanding.

Credit Agreement

As of March 31, 2013, no borrowings or letters of credit were outstanding under our $3 billion credit agreement. As described above, we have a $2 billion commercial paper program and maintain $2 billion of available borrowing capacity under our credit agreement in order to repay commercial paper borrowings in the event we are unable to repay those borrowings from other sources when they become due. As a result, at March 31, 2013, $1 billion of borrowing capacity was available for other purposes permitted by the credit agreement. The credit agreement includes customary covenants that, among other things, and subject to exceptions, limit our ability to create, assume or permit to exist liens on our property, assets and revenue (other than certain permitted liens) and require that we maintain a minimum consolidated interest coverage ratio, and also includes customary events of default.

As of March 31, 2013, we were in compliance with all covenants in our outstanding debt instruments.