Reinsurance - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) reinsurer	Dec. 31, 2020 USD ($) reinsurer
GMIB
Effects of Reinsurance [Line Items]
Annuitization election period	30 days
Percent of future claim payments reinsured	100.00%	100.00%
Number of external reinsurers \| reinsurer	3	3
Impact of non-performance risk
GMIB \| Other Contract [Member]
Effects of Reinsurance [Line Items]
GMIB liabilities	$ 572	729
Variable Annuity \| Berkshire Hathaway Life Insurance Company of Nebraska
Effects of Reinsurance [Line Items]
Percent of future claim payments reinsured	100.00%
Remaining overall limit under reinsurance agreement	$ 3,200
Other Current Assets
Effects of Reinsurance [Line Items]
Reinsurance recoverables	$ 129	$ 217

The period of time prior to a policy anniversary when an annuitization election must occur.

No definition available.

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- Definition

The number of external reinsurers underwriting credit risk ceded by the Company.

+ References

No definition available.

+ Details

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- Definition

Amount remaining of overall limit to claims covered under ceded reinsurance agreement.

+ References

No definition available.

+ Details

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- Definition

Percent of future claim payments reinsured under reinsurance agreement(s), net of existing retrocessional arrangements at the time agreement was made.

+ References

No definition available.

+ Details

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- Definition

Fair Value Measurement, Non-Performance Risk Adjustment

+ References

No definition available.

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- Definition

Reinsurance Recoverables, Net

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 210
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-Section 55
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
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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.

+ Details

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