The percentage of annuities subject to market value adjustment for discretionary withdrawals.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

No definition available.

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- Definition

Interest rate applied to policyholder contract deposits during the stated period.

+ References

No definition available.

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- Definition

The period over which withdrawal or surrender charges are generally calculated as either a percentage of account or declining dollar amount.

+ References

No definition available.

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- References

No definition available.

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- Definition

The liability as of the balance sheet date to the policyholders for deposits held under the terms of insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.13(a)(3))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 30
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49168914&loc=d3e13951-158433

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Reserve for Life-Contingent Contract Benefits and Contractholder Funds - Assumptions generally used in calculating the reserve for life-contingent (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Contractholder funds
Total contractholder funds	$ 18,592,000,000	$ 19,470,000,000	$ 20,542,000,000	$ 21,816,000,000
Key contract provisions relating to contractholder funds:
Reserve for life-contingent contract benefits with respect to deficiency	315,000,000	0
Interest-sensitive life insurance
Contractholder funds
Total contractholder funds	$ 7,387,000,000	7,312,000,000
Equity-indexed life insurance \| Minimum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	0.00%
Equity-indexed life insurance \| Maximum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	10.50%
Other life insurance \| Minimum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	1.00%
Other life insurance \| Maximum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	6.00%
Fixed annuities
Contractholder funds
Total contractholder funds	$ 10,790,000,000	11,893,000,000
Key contract provisions relating to contractholder funds:
Percent of fixed annuities subject to market value adjustment for discretionary withdrawals	16.70%
Fixed annuities \| Maximum
Key contract provisions relating to contractholder funds:
Period for withdrawal or surrender charges	10 years
Immediate fixed annuities \| Minimum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	0.00%
Immediate fixed annuities \| Maximum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	9.80%
Equity indexed fixed annuities
Key contract provisions relating to contractholder funds:
Period for withdrawal or surrender charges	20 years
Equity indexed fixed annuities \| Minimum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	(8.00%)
Equity indexed fixed annuities \| Maximum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	12.30%
Other fixed annuities \| Minimum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	0.10%
Other fixed annuities \| Maximum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	6.00%
Other investment contracts
Contractholder funds
Total contractholder funds	$ 415,000,000	$ 265,000,000
Other investment contracts \| Minimum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	1.50%
Other investment contracts \| Maximum
Key contract provisions relating to contractholder funds:
Contractholder funds, interest rate assumptions (as a percent)	10.30%