Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill and Other Intangible Assets [Line Items]
Goodwill impairment	$ 0	$ 0
Aggregate pre-tax amortization expense	319	362	$ 363
Continuing Operations [Member]
Goodwill and Other Intangible Assets [Line Items]
Aggregate pre-tax amortization expense	319	$ 360	$ 360
Pre-tax amortization expense, 2017	208
Pre-tax amortization expense, 2018	211
Pre-tax amortization expense, 2019	213
Pre-tax amortization expense, 2020	187
Pre-tax amortization expense, 2021	$ 138