Restructuring Costs (Tables)

3 Months Ended

Mar. 31, 2016

Restructuring Charges [Abstract]

Summary of separation activity

The following table summarizes the 2015 and 2016 employee separation activity:

(Millions of dollars)	Total
Liability balance at December 31, 2014	$	182
Increase in liability (separation charges)	641
Reduction in liability (payments)	(340		)
Liability balance at December 31, 2015	$	483
Increase in liability (separation charges)	31
Reduction in liability (payments)	(405		)
Liability balance at March 31, 2016	$	109