Investments - Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Investment Holdings [Line Items]
Limited partnership interests	$ 354,611	$ 328,516
Fair value of issued securities	5,839,560	7,515,318
FHLB funding agreements	$ 575,000	675,000
Investment Grade Rate	77.50%
Federal Home Loans Bank Of Chicago
Investment Holdings [Line Items]
Fair value of issued securities	$ 629,010	740,016
Governmental Agencies as Required by Law in Various States
Investment Holdings [Line Items]
Fair value of issued securities	$ 26,119	$ 17,695

Represents the federal home loan bank funding agreements.

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- Definition

Percentage of fair value of fixed maturity and equity securities with a gross unrealized loss having an investment grade rating at period end.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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Amount of investment in equity method investee and investment in and advance to affiliate.

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