Discontinued Operations - Additional Information (Details) - MCC Business - Discontinued Operations, Held-for-sale - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Discontinued Operations
Overhead expenses previously allocated	$ 7.0	$ 8.5	$ 13.7	$ 17.5
Excess capital and undistributed earnings			$ 160.0

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