Fair Value Information Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Inputs, Level 2 | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Company-owned life insurance (COLI)	$ 61	$ 57
Derivative assets	43	56
Derivative liabilities	46	42
Fair Value, Inputs, Level 3 | Preferred securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Redeemable Preferred Securities Of Subsidiaries Fair Value Disclosure	$ (58)	$ (64)