Variable Interest Entities - Non-Consolidated Variable Interest Entities (Detail) (USD $) In Millions, unless otherwise specified	Aug. 31, 2013 Agency mortgage- and asset-backed securitizations [Member]	Aug. 31, 2013 Non-agency mortgage- and asset-backed securitizations [Member]	Aug. 31, 2013 Variable Interest Entity Not Primary Beneficiary [Member] Collateralized loan obligations securitizations [Member]	Aug. 31, 2013 Variable Interest Entity Not Primary Beneficiary [Member] Successor [Member]	Aug. 31, 2013 Variable Interest Entity Not Primary Beneficiary [Member] Successor [Member] Collateralized loan obligations securitizations [Member]	Aug. 31, 2013 Variable Interest Entity Not Primary Beneficiary [Member] Successor [Member] Agency mortgage- and asset-backed securitizations [Member]	Aug. 31, 2013 Variable Interest Entity Not Primary Beneficiary [Member] Successor [Member] Non-agency mortgage- and asset-backed securitizations [Member]	Aug. 31, 2013 Variable Interest Entity Not Primary Beneficiary [Member] Successor [Member] Asset management vehicle [Member]	Aug. 31, 2013 Variable Interest Entity Not Primary Beneficiary [Member] Successor [Member] Private equity vehicles [Member]	Nov. 30, 2012 Variable Interest Entity Not Primary Beneficiary [Member] Predecessor [Member]	Nov. 30, 2012 Variable Interest Entity Not Primary Beneficiary [Member] Predecessor [Member] Collateralized loan obligations securitizations [Member]	Nov. 30, 2012 Variable Interest Entity Not Primary Beneficiary [Member] Predecessor [Member] Agency mortgage- and asset-backed securitizations [Member]	Nov. 30, 2012 Variable Interest Entity Not Primary Beneficiary [Member] Predecessor [Member] Non-agency mortgage- and asset-backed securitizations [Member]	Nov. 30, 2012 Variable Interest Entity Not Primary Beneficiary [Member] Predecessor [Member] Asset management vehicle [Member]	Nov. 30, 2012 Variable Interest Entity Not Primary Beneficiary [Member] Predecessor [Member] Private equity vehicles [Member]
Assets and Liabilities of Consolidated VIEs [Line Items]
Financial Statement Carrying Amount	$ 1,122.4	$ 647.0	$ 17.8	$ 1,842.2	$ 17.8	$ 1,122.4	$ 647.0	$ 3.1	$ 51.9	$ 2,456.5	$ 5.3	$ 1,579.1	$ 814.1	$ 3.0	$ 55.0
Maximum exposure to loss in non-consolidated VIEs				1,880.2	17.8	1,122.4	647.0	3.1	89.9	2,509.2	5.3	1,579.1	814.1	3.0	107.7
Size of the variable interest entity measured by total assets				$ 77,388.5	$ 1,784.5	$ 5,397.1	$ 69,737.1	$ 377.4	$ 92.4	$ 61,919.9	$ 499.7	$ 6,396.6	$ 54,436.2	$ 505.3	$ 82.1