Derivatives and Hedging Activities 1 (Details) - Interest Rate Contracts [Member] - Fair Value Hedging [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Expense [Member]
Derivative Instruments, Gains (Losses) [Line Items]
Fixed-rate long-term debt		$ 100	$ 91
Derivatives designated as hedging instruments		(129)	(102)
Total		$ (29)	$ (11)
Interest Expense [Member]
Derivative Instruments, Gains (Losses) [Line Items]
Fixed-rate long-term debt	$ 29
Derivatives designated as hedging instruments	(13)
Total	$ 16