Investments - KCG (Details) - KCG - USD ($) $ in Millions	3 Months Ended	6 Months Ended
May 31, 2017	Mar. 31, 2017	Dec. 31, 2016	May 31, 2017
Schedule of Equity Method Investments [Line Items]
Net earnings		$ 3.2	$ 196.2
Net gain on change in fair value of investment	$ (95.8)			$ (91.2)

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

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