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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Purchase amount of annuities | $ 21.0 |  |
Rental expense for operating leases for office space, equipment, and vehicles | $ 10.4 | $ 10.8 | $ 12.3
Capital Lease Agreements Expiration Period | 2022 |  |
Contractual Obligation Additional Investment in Alternative or Other Investments | $ 202.3 |  |
Common Stock [Member] |  |  |
Contractual Obligation | 17.8 |  |
Collateralized Loan Obligations [Member] |  |  |
Contractual Obligation | $ 40.4 |  |

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- Definition This item presents capital lease agreements expiring date. + References No definition available. + Details
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- Definition Contractual obligation to invest additional amounts in alternative and other investments. + References No definition available. + Details
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- Definition The amount of annuities purchased from life insurance companies to fulfill obligations under claim settlements that provide for periodic future payments to claimants. + References No definition available. + Details
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- Definition Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments. + References No definition available. + Details
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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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- Details
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- Details
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