Financial Instruments (Narrative) (Details) - Interest Rate Swap - USD ($) $ in Millions	Jun. 30, 2017	Jun. 30, 2016
Fair Value Hedging
Derivative [Line Items]
Derivative, notional amount	$ 1,813	$ 1,963
Cash Flow Hedging
Derivative [Line Items]
Derivative, notional amount		300
Designated as Hedging Instrument | Fair Value Hedging
Derivative [Line Items]
Derivative, notional amount	700	600
Derivatives, terminated notional amounts	600	250
Derivatives, matured notional amounts	250
Designated as Hedging Instrument | Cash Flow Hedging
Derivative [Line Items]
Derivative, notional amount	700	$ 300
Derivatives, terminated notional amounts	$ 1,000
Derivative Asset, Number of Instruments Held	0