Long-Term Debt And Capital Lease Obligation (Tables)

12 Months Ended

Dec. 31, 2017

Long-term Debt and Capital Lease Obligations [Abstract]

Book Value And Principal Amounts Of Long-Term Debt

This table summarizes the principal amounts of our long-term debt excluding unamortized discounts, none of which are encumbered by rating triggers:

(Dollars in millions)			Book value				Principal amount
Interest rate	Year of  issue		At December 31,				At December 31,
			2017		2016		2017		2016
6.900%	1998	Senior debentures, due 2028	$	26	$	26	$	28	$	28
6.920%	2005	Senior debentures, due 2028	391		391		391		391
6.125%	2004	Senior notes, due 2034	370		370		374		374
		Total	$	787	$	787	$	793	$	793

Capital Lease Payments Over Next Five Years

Below are the expected capital lease obligations that we expect to pay over the next six years:

(Dollars in millions)	Years ended December 31,
	2018		2019		2020		2021		2022		2023
Capital lease obligations	$	12	$	10	$	7	$	5	$	4	$	2