Income Taxes (Unaudited) (Tables)

3 Months Ended

Mar. 31, 2017

Income Tax Disclosure [Abstract]

Schedule of Income Tax Expense and Effective Income Tax Rates

	Three Months Ended March 31
$ in millions	2017			2016
Federal and foreign income tax expense	$	133		$	120
Effective income tax rate	17.2		%	17.8		%