Variable Interest Entities (Narrative) (Details) - USD ($) $ in Millions	Feb. 28, 2019	Nov. 30, 2018
Variable Interest Entity [Line Items]
Carrying Amount	$ 1,095.0	$ 746.4
Other investment vehicles
Variable Interest Entity [Line Items]
Carrying amount of equity investment	461.1	203.6
Unfunded equity commitment related to investments	10.4	11.1
Carrying Amount	461.1	203.6
Agency Mortgage-Backed Securitizations
Variable Interest Entity [Line Items]
Carrying Amount	2,821.0	2,913.0
Nonagency Mortgage- And Asset-Backed Securitizations
Variable Interest Entity [Line Items]
Carrying Amount	167.0	170.5
JCP Entities | Private Equity Vehicles
Variable Interest Entity [Line Items]
Equity commitments	139.3	139.3
Funded equity commitments	121.5	121.3
Carrying amount of equity investment	$ 31.6	$ 35.5