Severance (Tables)

12 Months Ended

Dec. 31, 2017

Restructuring and Related Activities [Abstract]

Schedule of changes in accrued liability for severance expenses

Changes in our accrued liability for severance expenses were as follows:

	Severance
	(Dollars in millions)
Balance at December 31, 2015	$	6
Accrued to expense	89
Payments, net	(43		)
Balance at December 31, 2016	52
Accrued to expense	14
Payments, net	(58		)
Balance at December 31, 2017	$	8