Supplementary Information (Tables)

12 Months Ended

Dec. 31, 2017

Supplemental Cash Flow Elements [Abstract]

Schedule of Cash Flow, Supplemental Disclosures

Cash paid for interest and income taxes was as follows:

	Year Ended December 31,
(Dollars in millions)	2017		2016		2015
Interest paid	$	538	$	467	$	477
Income taxes paid, net of refunds	87		161		331