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.

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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.

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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.

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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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Fair Value Measurements Level 4 Financial Instruments Not Carried At Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Jun. 01, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	$ 154,713	$ 150,146	$ 162,284
Assets, Fair Value Disclosure	116,376	109,799
Liabilities	152,161	148,141	$ 160,517
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	893	1,184
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Other Policyholder Funds and Benefits Payable [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	6,049	6,186
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Investment Contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Liabilities	1	185
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Policy Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	1,467	1,441
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Mortgages [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets	2,241	2,100
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Other Policyholder Funds and Benefits Payable [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure	5,912	5,888
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Investment Contracts [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial Liabilities Fair Value Disclosure	1	185
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	1,467	1,441
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	$ 2,331	$ 2,125