Reserve for Life-Contingent Contract Benefits and Contractholder Funds (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Reserve for life-contingent benefits:
Total reserve for life-contingent contract benefits	$ 12,247	$ 12,380
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Premium deficiency reserve	0	28
Structured settlement annuities
Reserve for life-contingent benefits:
Total reserve for life-contingent contract benefits	$ 6,673	6,682
Structured settlement annuities \| Minimum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	2.70%
Structured settlement annuities \| Maximum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	9.00%
Other immediate fixed annuities
Reserve for life-contingent benefits:
Total reserve for life-contingent contract benefits	$ 2,041	2,250
Other immediate fixed annuities \| Minimum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	0.00%
Other immediate fixed annuities \| Maximum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	11.50%
Traditional life insurance
Reserve for life-contingent benefits:
Total reserve for life-contingent contract benefits	$ 2,584	2,521
Traditional life insurance \| Minimum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	2.50%
Traditional life insurance \| Maximum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	11.30%
Accident and health insurance
Reserve for life-contingent benefits:
Total reserve for life-contingent contract benefits	$ 844	830
Accident and health insurance \| Minimum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	3.00%
Accident and health insurance \| Maximum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	7.00%
Other
Reserve for life-contingent benefits:
Total reserve for life-contingent contract benefits	$ 105	$ 97
Other \| Minimum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	2.10%
Other \| Maximum
Key assumptions generally used in calculating the reserve for life-contingent contract benefits:
Life contingent contract benefits, interest rate assumptions (as a percent)	5.80%

Insurance reserve adjustment included in accumulated other comprehensive income (loss) which represents the amount by which the reserve balance would increase if the net unrealized gains in the applicable product portfolios were realized and reinvested at current lower interest rates, resulting in a premium deficiency.

No definition available.

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Interest rate in the range of interest rates used to calculate future benefits to be paid to or on behalf of policyholders and related expenses less the present value of future net premiums using assumptions such as estimates of expected investment yields, mortality, morbidity, terminations and expenses, applicable at the time the insurance contracts are made and cost of settling insured claims and cost incurred in the claim settlement process.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 25
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=28366191&loc=d3e13145-158430

Reference 2: 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)(1))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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