Investments - Summary of Selected Financial Information for Berkadia (Details) - Berkadia Commercial Mortgage, LLC - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Aug. 31, 2019	Aug. 31, 2019	Nov. 30, 2018
Schedule of Equity Method Investments [Line Items]
Our total equity balance	$ 270.5	$ 270.5	$ 245.2
Net earnings	$ 53.8	$ 160.3

The amount of net income (loss) reported by an equity method investment of the entity.

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