Supplemental Income Statement Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Interest expense	$ 132	$ 123
Interest income	(4)	(10)
Pension and postretirement net periodic benefit cost (benefit)	(79)	(38)
Total	49	$ 75
Fixed rate medium term note due 2022
Loss on extinguishment of debt	$ 11

Amount of net periodic benefit cost (credit) for defined benefit plan.

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