Short-Term Financing (Details) - USD ($)	3 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Short-term Debt [Line Items]
Short-term Debt	$ 0
Maturities of commercial paper range	overnight to up to 364 days
Commercial Paper	$ 0	$ 0
Commercial Paper Weight Average Maturity	2 days
Maturities of short-term funding agreements	overnight to up to five business days
Obligations under reverse repurchase agreements	$ 0	0
364-Day Credit Agreement [Member]
Short-term Debt [Line Items]
Maximum borrowing capacity under credit facilities	$ 3,250,000,000
Term of credit	364 days
Expiration date of credit facilities	Jun. 16, 2017
Credit Facility Expiring In June Two Thousand Nineteen [Member]
Short-term Debt [Line Items]
Maximum borrowing capacity under credit facilities	$ 2,250,000,000
Term of credit	5 years
Expiration date of credit facilities	Jun. 17, 2020
Line of credit facility potentially available increase in maximum borrowing capacity	$ 500,000,000
Credit Facility Expiring In June Two Thousand Twenty [Member]
Short-term Debt [Line Items]
Maximum borrowing capacity under credit facilities	$ 3,750,000,000
Term of credit	5 years
Expiration date of credit facilities	Jun. 18, 2021
Line of credit facility potentially available increase in maximum borrowing capacity	$ 500,000,000
Commercial Paper [Member]
Short-term Debt [Line Items]
Aggregate amount of commercial paper issuable under the short-term commercial paper program	9,250,000,000
Short-term Debt, Average Outstanding Amount	$ 4,100,000,000	$ 3,500,000,000
Debt Instrument, Interest Rate During Period	0.40%	0.20%
Reverse Repurchase Agreements [Member]
Short-term Debt [Line Items]
Short-term Debt, Average Outstanding Amount	$ 359,300,000	$ 485,600,000
Debt Instrument, Interest Rate During Period	0.60%	0.40%