Investments - Berkadia - Narrative (Details) - Berkadia Commercial Mortgage, LLC - USD ($) $ in Millions	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019	Nov. 30, 2019	Oct. 01, 2018
Schedule of Equity Method Investments [Line Items]
Ownership percentage				50.00%
Percentage of profits received from joint venture				45.00%
Purchase commitment amount	$ 328.3		$ 360.4
Distribution received from equity method investment	$ 36.2	$ 17.3

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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