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Face (par) amount of debt instrument at time of issuance.

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Debt Instrument, Redemption Price, Accrued and Unpaid Interest

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Borrowings - Note Issuances (Details)	Jun. 01, 2016 USD ($)	May 31, 2017 USD ($)	May 31, 2017 EUR (€)
Total $6.0 billion debt issuance
Debt Instrument [Line Items]
Face amount		$ 6,000,000,000
Fair value of the notes		6,100,000,000
Carrying value of the notes		6,000,000,000
Net proceeds from notes payable	$ 6,000,000,000
Total issuance costs	$ 30,000,000
Percentage of principal amount of fixed rate notes can be redeemed	101.00%
Debt Instrument, Redemption Price, Accrued and Unpaid Interest	$ 1,000,000
Total $8.0 billion debt issuance
Debt Instrument [Line Items]
Face amount		8,000,000,000
Fair value of the notes		7,500,000,000
Carrying value of the notes		7,200,000,000
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		800,000,000
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		$ 300,000,000