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Fair Value Measurements (Tables)
12 Months Ended
Dec. 31, 2020
Fair Value Disclosures [Abstract]  
Summary of the fair value of financial instruments The estimated fair values of our other financial instruments, all of which are categorized in Level 1 of the fair value hierarchy, as of December 31, 2020 and 2019 have been calculated based upon available market information, and were as follows:  
December 31, 2020December 31, 2019
Carrying
Amount
Fair
Value 
Carrying
Amount 
Fair
Value 
Senior notes$6,965 $7,470 $7,755 $8,176