Fair Value Measurements And Financial Instruments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Mar. 31, 2012	Mar. 31, 2011	Jun. 30, 2011
Derivative [Line Items]
Maximum duration for commodity futures and swap contracts, months				18
Maximum duration for interest rate forward contracts, months				6
Maximum duration for foreign currency contracts, months				12
Derivative financial instruments designated as fair value hedges	0		0	0	0
Settlement of interest rate lock		$ 36
Notional value of commodity derivatives	42			42		44
Estimated fair value of long-term debt	2,606			2,606		2,303
Diesel Fuel Commodity Contract [Member]
Derivative [Line Items]
Notional value of commodity derivatives	0			0		3
Jet Fuel Commodity Contract [Member]
Derivative [Line Items]
Notional value of commodity derivatives	20			20		22
Soybean Oil Commodity Contract [Member]
Derivative [Line Items]
Notional value of commodity derivatives	19			19		16
Crude Oil Commodity Contract [Member]
Derivative [Line Items]
Notional value of commodity derivatives	3			3		3
Canada Foreign Currency Forward Contracts [Member]
Derivative [Line Items]
Notional value of foreign currency derivatives	9			9		28
Australia Foreign Currency Forward Contracts [Member]
Derivative [Line Items]
Notional value of foreign currency derivatives	6			6		13
Interest Rate Contracts [Member]
Derivative [Line Items]
Notional value of interest rate forward contracts	0			0		300
Maximum [Member]
Derivative [Line Items]
Estimated amount of the existing net gain to be reclassified into earnings, in the next 12 months				$ 1