v3.24.1.u1
Fair Value of Financial Instruments
3 Months Ended
Mar. 31, 2024
Fair Value Disclosures [Abstract]  
Fair Value of Financial Instruments Fair Value of Financial Instruments
The carrying amount of cash and equivalents, receivables, and accounts payable, as reflected in the condensed consolidated balance sheets, approximates fair value due to the short maturities of these instruments.

The carrying amount and fair value of our total debt is as follows:
March 31, 2024December 31, 2023
Millions of dollarsLevel 1Level 2Total fair valueCarrying valueLevel 1Level 2Total fair valueCarrying value
Total debt$7,294 $361 $7,655 $7,637 $7,419 $378 $7,797 $7,636 

In the first three months of 2024, the fair value of our total debt decreased as a result of higher bond yields.

Our debt categorized within level 1 on the fair value hierarchy is calculated using quoted prices in active markets for identical liabilities with transactions occurring on the last two days of period-end. Our debt categorized within level 2 on the fair value hierarchy is calculated using significant observable inputs for similar liabilities where estimated values are determined from observable data points on our other bonds and on other similarly rated corporate debt or from observable data points of transactions occurring prior to two days from period-end and adjusting for changes in market conditions. Differences between the periods presented in our level 1 and level 2 classification of our long-term debt relate to the timing of when third party market transactions on our debt are executed. We have no debt categorized within level 3 on the fair value hierarchy.