Commitments, Contingencies and Guarantees - Commitments and Contingencies (Detail) $ in Millions	6 Months Ended
	May 31, 2017 USD ($)
Other Commitments [Line Items]
2017	$ 7,367.6
2018	405.2
2019 and 2020	360.2
2021 and 2022	92.6
2023 and Later	152.4
Maximum Payout	$ 8,378.0
Guarantor obligation settled period (in days)	3 days
Equity commitments [Member]
Other Commitments [Line Items]
2017	$ 0.0
2018	9.4
2019 and 2020	11.1
2021 and 2022	0.0
2023 and Later	140.1
Maximum Payout	160.6
Loan commitments [Member]
Other Commitments [Line Items]
2017	45.0
2018	261.9
2019 and 2020	15.6
2021 and 2022	54.9
2023 and Later	0.0
Maximum Payout	377.4
Mortgage-related and other purchase commitments [Member]
Other Commitments [Line Items]
2017	0.0
2018	0.0
2019 and 2020	191.2
2021 and 2022	0.0
2023 and Later	0.0
Maximum Payout	191.2
Forward starting reverse repos [Member]
Other Commitments [Line Items]
2017	4,768.1
2018	0.0
2019 and 2020	0.0
2021 and 2022	0.0
2023 and Later	0.0
Maximum Payout	4,768.1
Forward starting repos [Member]
Other Commitments [Line Items]
2017	2,464.5
2018	0.0
2019 and 2020	0.0
2021 and 2022	0.0
2023 and Later	0.0
Maximum Payout	2,464.5
Other unfunded commitments [Member]
Other Commitments [Line Items]
2017	90.0
2018	133.9
2019 and 2020	142.3
2021 and 2022	37.7
2023 and Later	12.3
Maximum Payout	$ 416.2