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Commitments and Contingencies Investments Contractual Obligations (Tables) | 12 Months Ended
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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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- Definition Tabular disclosure of commitments that may require us to invest additional amounts into our investment portfolio. + References No definition available. + Details
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- References No definition available. + Details
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