Fair value by balance sheet grouping table (Tables)

3 Months Ended

Mar. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Carrying Values and Estimated Fair Values of Debt Instruments

The carrying amount and fair value of our total debt, including short-term borrowings and current maturities of long-term debt, is as follows:

	March 31, 2019								December 31, 2018
Millions of dollars	Level 1		Level 2		Total fair value		Carrying value		Level 1		Level 2		Total fair value		Carrying value
Total debt	$	8,769	$	2,621	$	11,390	$	10,332	$	6,726	$	4,041	$	10,767	$	10,348