Fair Value Information (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Redeemable Preferred Securities Of Subsidiaries Fair Value Disclosure	$ 61	$ 61
Fair Value, Measurements, Recurring | Net Asset Value or Its Equivalent
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Company-owned life insurance (“COLI”)	68	68
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivatives Assets	30	27
Derivatives Liability	$ 69	$ 51