Borrowings - Note Issuances (Details) - Nov. 30, 2017	USD ($)	EUR (€)
Total $6.0 billion debt issuance
Debt Instrument [Line Items]
Face amount	$ 6,000,000,000
Fair value of the notes	2,500,000,000
Carrying value of the notes	2,500,000,000
Total $8.0 billion debt issuance
Debt Instrument [Line Items]
Face amount	8,000,000,000
Fair value of the notes	6,700,000,000
Carrying value of the notes	6,500,000,000
Total 700 million pounds debt issuance
Debt Instrument [Line Items]
Face amount \| €		€ 700,000,000.0
Fair value of the notes	1,000,000,000
Carrying value of the notes	900,000,000
Total 750 million euros debt issuance
Debt Instrument [Line Items]
Face amount \| €		€ 750,000,000.00
Fair value of the notes	900,000,000
Carrying value of the notes	900,000,000
Total $4.0 billion debt issuance
Debt Instrument [Line Items]
Face amount	4,000,000,000
Fair value of the notes	1,700,000,000
Carrying value of the notes	1,700,000,000
Total $1.0 billion debt issuance
Debt Instrument [Line Items]
Face amount	1,000,000,000
Fair value of the notes	300,000,000
Carrying value of the notes	$ 200,000,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-Name Accounting Standards Codification
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