Fair Value Measurements Level 4 Financial Instruments Not Carried At Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	$ 175,350	$ 191,775
Assets, Fair Value Disclosure	144,439	161,030
Liabilities	167,188	182,484
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	2,411	2,998
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Policy Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	1,446	1,430
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Mortgages [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	2,995	3,280
Estimate of Fair Value Measurement [Member] \| Other Policyholder Funds and Benefits Payable [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure	6,802	7,353
Estimate of Fair Value Measurement [Member] \| Investment Contracts [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure	682	851
Estimate of Fair Value Measurement [Member] \| Other Liabilities [Member] \| Embedded Derivative Financial Instruments [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure	38	68
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Policy Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	1,446	1,430
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Mortgages [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	2,918	3,109
Reported Value Measurement [Member] \| Other Policyholder Funds and Benefits Payable [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	6,611	7,134
Reported Value Measurement [Member] \| Other Liabilities [Member] \| Embedded Derivative Financial Instruments [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	38	68
Reported Value Measurement [Member] \| JAPAN \| Hartford Life Insurance K.K. [Member] \| Investment Contracts [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	$ 619	$ 763

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.18)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 12
-Article 7

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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