Policyholders' Liabilities (Future Policy Benefits) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Liability for Future Policy Benefits [Abstract]
Life insurance – domestic	$ 74	$ 800
Individual and group annuities and supplementary contracts	1,021,854	970,936
Other contract liabilities	8,347,058	8,160,833
Total future policy benefits	$ 9,368,986	$ 9,132,569

Amount of accrued obligation to policyholders that relates to insured events for long-duration contracts.

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Amount of accrued obligation to policyholders that relates to insured events under individual and group annuities and supplementary insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Section 25
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Amount of accrued obligation to policyholders that relates to insured events under long-term life insurance contracts.

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Amount of accrued obligation to policyholders that relates to insured events under other insurance contracts.

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