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Commitments and Contingencies Investments Contractual Obligations (Tables)

12 Months Ended

Dec. 31, 2019

Commitments and Contingencies Disclosure [Abstract]

Investments Classified by Contractual Maturity Date [Table Text Block]

($ in millions)		Amount of Obligation				Year of Expiration of Obligation
Alternative and other investments		$	219.2			2036
Non-publicly traded collateralized loan obligations in our fixed income securities portfolio		35.4				2030
Non-publicly traded common stock within our equity portfolio		3.9				2023
Commercial mortgage loans		10.0				Less than 1 year
Privately-placed corporate securities		15.0				Less than 1 year
Total		$	283.5

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