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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

X

- 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.

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X

- 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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X

- 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.

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X

- 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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