Derivatives and Hedging Activities (Details 1) - Interest Rate Contracts [Member] - Fair Value Hedging [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Other Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged item		$ 50
Derivatives designated as hedging instruments		(75)
Total		$ (25)
Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Hedged item	$ 210
Derivatives designated as hedging instruments	(191)
Total	$ 19