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Nature of Operations and Significant Accounting Policies - Contractholder and Policyholder Liabilities (Details) - Individual Life insurance	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Contractholder and Policyholder Liabilities
Participating business as a percentage of life insurance in force (as a percent)	4.00%	5.00%	6.00%
Participating business as a percentage of life insurance policies in force (as a percent)	18.00%	20.00%	23.00%
Participating business as a percentage of life insurance premiums (as a percent)	22.00%	24.00%	21.00%

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- Definition

This percent places participating policies in the numerator and total number of life insurance policies in force in the denominator. Participating insurance contracts allow policyholders to share in the experience of the entity, primarily through policy dividends.

+ References

No definition available.

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- References

No definition available.

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- Definition

Percentage of participating insurance contract to insurance contracts in force.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 50
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6483535&loc=d3e16392-158451

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.14(b)(1))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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- Definition

Percentage of participating insurance to premium income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 50
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6483535&loc=d3e16392-158451

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(14)(b)(2))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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