Derivative Instruments and Hedging Activities (Changes in AOCI Related to Derivative Gains (Losses)) (Details) (USD $) In Millions, unless otherwise specified			3 Months Ended		9 Months Ended
	Mar. 31, 2012	Jun. 30, 2011	Mar. 31, 2012 Deferred Gain (Loss) On Hedging Activities [Member]	Mar. 31, 2011 Deferred Gain (Loss) On Hedging Activities [Member]	Mar. 31, 2012 Deferred Gain (Loss) On Hedging Activities [Member]	Mar. 31, 2011 Deferred Gain (Loss) On Hedging Activities [Member]
Balance of Accumulated Other Comprehensive Income (Loss) at beginning of period	$ (423)	$ 176	$ 30	$ 43	$ 29	$ 30
Unrealized gains (losses)			(54)	61	(32)	308
Losses (gains) reclassified to earnings			13	(101)	(6)	(326)
Tax effect			15	16	13	7
Balance of Accumulated Other Comprehensive Income (Loss) at End of period	$ (423)	$ 176	$ 4	$ 19	$ 4	$ 19