Commitments, Contingencies and Guarantees - Guarantees (Detail) (USD $) In Millions, unless otherwise specified	May 31, 2014
Guarantee Obligations [Line Items]
Notional/Maximum Payout	$ 3,252.0
Derivative contracts-non-credit related [Member]
Guarantee Obligations [Line Items]
2014	37,589.9
2015	1,141.8
2016 and 2017	43.7
2018 and 2019	1.2
2020 and Later	534.5
Notional/Maximum Payout	39,311.1
Written derivative contracts-credit related [Member]
Guarantee Obligations [Line Items]
2014
2015
2016 and 2017
2018 and 2019	420.8
2020 and Later
Notional/Maximum Payout	420.8
Derivatives [Member]
Guarantee Obligations [Line Items]
2014	37,589.9
2015	1,141.8
2016 and 2017	43.7
2018 and 2019	422.0
2020 and Later	534.5
Notional/Maximum Payout	$ 39,731.9