v3.22.4
Debt
 12 Months Ended
Dec. 31, 2022
Debt Disclosure [Abstract]  
Debt Debt
Short-Term Debt
We have a debt financing program of up to $10.0 billion through the issuance of commercial paper. Net proceeds from this program are used for general corporate purposes. We had no commercial paper outstanding as of December 31, 2021 and 2022.
Our short-term debt balance also includes the current portion of certain long-term debt.
Long-Term Debt
Total outstanding debt is summarized below (in millions, except percentages):
Effective Interest RateAs of December 31,
MaturityCoupon Rate20212022
Debt
2014-2020 Notes issuances2024 - 2060
0.45% - 3.38%
0.57% - 3.38%
$13,000 $13,000 
Future finance lease payments, net and other (1)
2,086 2,142 
      Total debt15,086 15,142 
Unamortized discount and debt issuance costs(156)(143)
Less: current portion of future finance lease payments, net and other current debt(1)(2)
(113)(298)
       Total long-term debt$14,817 $14,701 
(1)Future finance lease payments are net of imputed interest.
(2)Total current portion of long-term debt is included within other accrued expenses and current liabilities. See Note 7 for further details.
The notes in the table above are fixed-rate senior unsecured obligations and generally rank equally with each other. We may redeem the notes at any time in whole or in part at specified redemption prices. The effective interest rates are based on proceeds received with interest payable semi-annually.
The total estimated fair value of the outstanding notes was approximately $12.4 billion and $9.9 billion as of December 31, 2021 and December 31, 2022, respectively. The fair value was determined based on observable market prices of identical instruments in less active markets and is categorized accordingly as Level 2 in the fair value hierarchy.
As of December 31, 2022, the aggregate future principal payments for long-term debt, including finance lease liabilities, for each of the next five years and thereafter were as follows (in millions):
2023$221 
20241,156
20251,159
20262,163
20271,166
Thereafter9,447
Total$15,312 
Credit Facility
As of December 31, 2022, we had $10.0 billion of revolving credit facilities, $4.0 billion expiring in April 2023 and $6.0 billion expiring in April 2026. The interest rates for all credit facilities are determined based on a formula using certain market rates, as well as our progress toward the achievement of certain sustainability goals. No amounts were outstanding under the credit facilities as of December 31, 2021 and 2022