Sale of Accounts Receivable (Details) (USD $)	1 Months Ended	3 Months Ended	9 Months Ended
	Mar. 31, 2012	Mar. 31, 2012	Mar. 31, 2012
Sale of Accounts Receivable
Maximum amount provided under accounts receivable securitization facility excluded in lines of credit	$ 1,000,000,000	$ 1,000,000,000	$ 1,000,000,000
Receivables sold under securitization facility derecognized during the period	1,700,000,000	1,700,000,000	1,700,000,000
Cash payments received in exchange for the transfer of accounts receivable		1,000,000,000	1,000,000,000
Deferred receivables consideration	710,000,000	710,000,000	710,000,000
Proceeds received in cash from transfers of receivables to purchasers	355,000,000
Risk of loss on sale of accounts receivable	700,000,000	700,000,000	700,000,000
Loss on transfer of accounts receivables to purchasers		$ 1,000,000	$ 1,000,000