Cash Flow Information	12 Months Ended
Cash Flow Information	Dec. 31, 2021
Cash Flow Information [Abstract]
Cash Flow Information	Note 19—Cash Flow Information Millions of Dollars 2021 2020 2019 Noncash Investing Activities Increase (decrease) in PP&E related to an increase (decrease) in asset retirement obligations $ 442 (116) 205 Cash Payments Interest $ 924 785 810 Income taxes 856 905 2,905 Net Sales (Purchases) of Investments Short-term investments purchased $ (5,554) (12,435) (4,902) Short-term investments sold 8,810 12,015 2,138 Investments and long-term receivables purchased (279) (325) (146) Investments and long-term receivables sold 114 87 - $ 3,091 (658) (2,910) The following items are included in the “Cash Flows from Operating Activities” section of our consolidated cash flows. In 2021, we made a total of $ 297 million in contributions to our U.S. qualified pension plan. In 2019, we made a $ 324 million contribution to our U.K. pension plan. We collected $ 330 million in 2019 from PDVSA under settlement agreements related to an award issued by the ICC Tribunal in 2018. For more information on these settlements, see Note 11 . See Note 3 and Note 12 for additional information on cash and non-cash changes to our consolidated balance sheet associated with our Concho acquisition.