Liability for Closed Locations (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended	12 Months Ended
Feb. 29, 2012	Feb. 28, 2011	Feb. 29, 2012	Feb. 28, 2011	Aug. 31, 2011
Notes to Financial Statements [Abstract]
Charges recorded during the period for facilities that were closed or relocated under long-term leases	$ 3	$ 25	$ 14	$ 37
Changes in reserve for facility closings and related lease termination charges [Rollforward]
Facility closings and related lease termination charges balance - beginning of period			145	151	151
Provision for present value of non-cancellable lease payments of closed facilities			4	31	49
Assumptions about future sublease income, terminations, and changes in interest rates			(4)	(4)	(19)
Interest accretion			14	10	24
Cash payments, net of sublease income			(28)	(32)	(60)
Facility closings and related lease termination charges balance - end of period	$ 131	$ 156	$ 131	$ 156	$ 145

Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 14

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 146

-Paragraph 6

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- Definition

Recorded charges during the period relating to facilities that were closed or relocated under long-term leases.

+ References

No definition available.

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- Definition

Liability as of the balance sheet date for facility closings and related lease termination charges. This liability is based on the present value of future rent obligations and other related costs (net of estimated sublease rent) to the first lease option date.

+ References

No definition available.

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- Definition

Amount of any reversal and other adjustment made during the period to the amount of a previously accrued liability for facility closings and related lease termination charges for assumptions about future sublease income, terminations and changes in interest rates.

+ References

No definition available.

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- Definition

Amount of cash paid in the period to fully or partially settle a specified, previously accrued type of facility closing or related lease termination cost, net of sublease income.

+ References

No definition available.

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- Definition

Reserve increase representing the amount charged against earnings in the period for the present value of non-cancellable lease payments of closed facilities.

+ References

No definition available.

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