Reinsurance - In-force Life Insurance (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reinsurance Disclosures [Abstract]
Direct life insurance in force	$ 767,001,938	$ 731,822,070	$ 696,939,187
Amounts ceded to other companies	(668,446,638)	(643,364,460)	(616,255,740)
Net life insurance in force	$ 98,555,300	$ 88,457,610	$ 80,683,447
Percentage of reinsured life insurance in force	87.00%	88.00%

Ratio of insurance contracts that are subject to reinsurance participation to all contracts in force.

No definition available.

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- Definition

Amount of life insurance issued and outstanding ceded to other entities. Includes, but not limited to, dividends and adjustments to face value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17)
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

+ Details

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- Definition

Amount before contracts ceded to other entities and contracts assumed by the entity of life insurance issued and outstanding. Includes, but not limited to, dividends and adjustments to face value.

+ References

+ Details

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- Definition

Amount after contracts ceded to other entities and contracts assumed by the entity of life insurance issued and outstanding. Includes, but not limited to, dividends and adjustments to face value.

+ References

+ Details

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- References

No definition available.

+ Details

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