Income Taxes (Tables)

9 Months Ended

Sep. 30, 2018

Income Tax Disclosure [Abstract]

Schedule of components of income tax expense (benefit)

Our income tax expense and effective tax rate for the three and nine months ended September 30 were as follows:

	Three months ended September 30,						Nine months ended September 30,
(dollars in millions)	2018			2017			2018			2017
Income tax expense	$	15		$	27		$	37		$	76
Effective tax rate	20.5		%	29.0		%	19.6		%	31.3		%