Variable Interest Entities - Additional Information (Details) - USD ($) $ in Millions	Aug. 31, 2019	Nov. 30, 2018
Related party private equity vehicles | JCP Entities
Variable Interest Entity [Line Items]
Equity investments	$ 139.3	$ 139.3
Funded equity commitments	121.7	121.3
Carrying amount of equity investment	28.7	35.5
Other investment vehicles
Variable Interest Entity [Line Items]
Equity investments	400.2	112.2
Funded equity commitments	389.2	108.1
Carrying amount of equity investment	399.1	95.0
Agency mortgage-backed securities
Variable Interest Entity [Line Items]
Carrying amount	1,712.9	2,913.0
Non-agency mortgage and other asset-backed securities
Variable Interest Entity [Line Items]
Carrying amount	$ 191.2	$ 170.5