Fair Value (Financial Instruments Carried at Other Than Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Assets
Policy loans	$ 938	$ 898
Liabilities
Separate account liabilities	81,690	78,880
Carrying Value
Assets
Mortgage loans	22,475	22,877
Policy loans	938	898
Other invested assets	260	341
Premiums, reinsurance and other receivables	7,431	5,915
Liabilities
Policyholder account balances	31,362	31,223
Short-term debt		125
Long-term debt	836	838
Other liabilities	1,191	1,009
Separate account liabilities	1,148	1,022
Estimated Fair Value
Assets
Mortgage loans	20,578	20,760
Policy loans	973	930
Other invested assets	260	341
Premiums, reinsurance and other receivables	7,578	6,065
Liabilities
Policyholder account balances	30,501	30,303
Short-term debt		125
Long-term debt	781	742
Other liabilities	1,191	1,009
Separate account liabilities	1,148	1,022
Estimated Fair Value \| Level 1
Assets
Mortgage loans	0	0
Policy loans	0	0
Other invested assets	0	0
Premiums, reinsurance and other receivables	0	0
Liabilities
Policyholder account balances	0	0
Short-term debt		0
Long-term debt	0	0
Other liabilities	0	0
Separate account liabilities	0	0
Estimated Fair Value \| Level 2
Assets
Mortgage loans	0	0
Policy loans	479	477
Other invested assets	245	201
Premiums, reinsurance and other receivables	80	77
Liabilities
Policyholder account balances	0	0
Short-term debt		0
Long-term debt	26	28
Other liabilities	438	212
Separate account liabilities	1,148	1,022
Estimated Fair Value \| Level 3
Assets
Mortgage loans	20,578	20,760
Policy loans	494	453
Other invested assets	15	140
Premiums, reinsurance and other receivables	7,498	5,988
Liabilities
Policyholder account balances	30,501	30,303
Short-term debt		125
Long-term debt	755	714
Other liabilities	753	797
Separate account liabilities	$ 0	$ 0

Total amount of mortgage loans not valued on a recurring basis as of the balance sheet date.

No definition available.

Name:	bhl_FairValueMortgageLoansNetNotOnRecurringBasis
Namespace Prefix:	bhl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of other investments not otherwise specified in the taxonomy.

+ References

No definition available.

+ Details

Name:	bhl_OtherInvestmentsFairValueDisclosure
Namespace Prefix:	bhl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of the liability of policyholders for deposits held under the terms of insurance contracts.

+ References

No definition available.

+ Details

Name:	bhl_PolicyholderContractDepositsFairValueDisclosure
Namespace Prefix:	bhl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_FinancialInstrumentsFinancialAssetsBalanceSheetGroupingsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_FinancialInstrumentsFinancialLiabilitiesBalanceSheetGroupingsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(e))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

+ Details

Name:	us-gaap_LoansInsurancePolicy
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of other liabilities.

+ References

No definition available.

+ Details

Name:	us-gaap_OtherLiabilitiesFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of receivables, including, but not limited to, trade account receivables, note receivables, and loan receivables.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

+ Details

Name:	us-gaap_ReceivablesFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of liability for variable contract in which all or portion of contract holder's funds is allocated to specific separate account and supported by assets held in separate account.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480078/944-80-55-18

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480109/944-80-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480141/944-80-45-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(18))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480109/944-80-50-2

+ Details

Name:	us-gaap_SeparateAccountsLiability
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_ShorttermDebtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_FairValueByMeasurementBasisAxis=us-gaap_CarryingReportedAmountFairValueDisclosureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByMeasurementBasisAxis=us-gaap_EstimateOfFairValueFairValueDisclosureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: