Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Borrowings - Additional Information (Details)			3 Months Ended
Borrowings - Additional Information (Details)	Jun. 05, 2017 USD ($)	Jun. 01, 2016 USD ($) tranche	Nov. 30, 2016 USD ($)	Jun. 01, 2018 USD ($)	Nov. 30, 2017 USD ($)	Aug. 31, 2017 USD ($)	Aug. 24, 2017 USD ($)	Feb. 01, 2017 USD ($)
Total $6.0 billion debt issuance
Debt Instrument [Line Items]
Proceeds from notes payable		$ 6,000,000,000
Number of tranches \| tranche		5
Redemption price, percentage of principal amount redeemed	101.00%
Redemption price, accrued and unpaid interest	$ 1,000,000
Medium-term Notes \| 2017 Term Loan Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 1,000,000,000
Borrowing outstanding					$ 30,000,000
Commercial Paper
Debt Instrument [Line Items]
Average daily short-term borrowings			$ 620,000,000
Weighted-average interest rate			1.46%
Balance outstanding					0	$ 0
Revolving Credit Facility \| February 2017 Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity								$ 1,000,000,000.0
Borrowing outstanding					$ 0
Revolving Credit Facility \| August 2017 Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 1,000,000,000
Forecast \| Medium-term Notes \| 2017 Term Loan Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 500,000,000
Term Loan \| Maximum
Debt Instrument [Line Items]
Debt to total capitalization ratio					0.6