Fair Value of Financial Instruments Fair value by balance sheet grouping table (Tables)

6 Months Ended

Jun. 30, 2017

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:

	June 30, 2017								December 31, 2016
Millions of dollars	Level 1		Level 2		Total fair value		Carrying value		Level 1		Level 2		Total fair value		Carrying value
Total debt	$	572	$	11,738	$	12,310	$	11,152	$	753	$	12,812	$	13,565	$	12,384