Commitments and Contingencies - Purchase Obligations (Details) (USD $)	12 Months Ended
	Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2011
Unrecorded Unconditional Purchase Obligation [Line Items]
Long-term unconditional purchase obligations, Total	$ 510,705,000
Long-term unconditional purchase obligations, Less than 1 Year	63,387,000
Long-term unconditional purchase obligations, 1 - 3 Years	137,237,000
Long-term unconditional purchase obligations, 3 - 5 Years	89,700,000
Long-term unconditional purchase obligations, More than 5 Years	220,381,000
Other contractual obligations, Total	4,871,767,000
Other contractual obligations, Less than 1 Year	4,713,927,000
Other contractual obligations, 1 - 3 Years	80,454,000
Other contractual obligations, 3 - 5 Years	10,459,000
Other contractual obligations, More than 5 Years	66,927,000
Total purchase obligations, Total	5,382,472,000	6,300,000,000
Total purchase obligations, Less than 1 Year	4,777,314,000
Total purchase obligations, 1 - 3 Years	217,691,000
Total purchase obligations, 3 - 5 Years	100,159,000
Total purchase obligations, More than 5 Years	287,308,000
Long-term unconditional purchase obligations, minimum amount required	423,900,000
Long-term unconditional purchase obligations, period amount purchase	$ 62,400,000	$ 47,800,000	$ 60,800,000