Reflects the number of financing receivables of recorded investment that are past due at the balance sheet date.

No definition available.

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Namespace Prefix:	bhl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Reflects the number of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

No definition available.

+ Details

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Namespace Prefix:	bhl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of all mortgage loans that are classified as performing.

+ References

No definition available.

+ Details

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Namespace Prefix:	bhl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of any significant purchases of financing receivables during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

Name:	us-gaap_FinancingReceivableSignificantPurchases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

+ Details

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

- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=bhl_AgriculturalPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_RealEstateLoanMember
Namespace Prefix:
Data Type:	na
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Period Type:

Investments (Mortgage Loans - Narrative) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019 USD ($) Contracts	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) Contracts
Financing Receivable, Recorded Investment, Past Due [Line Items]
Percentage of mortgage loans classified as performing	99.00%		99.00%
Commercial
Financing Receivable, Recorded Investment, Past Due [Line Items]
Number of loans past due \| Contracts	0		0
Number of loans in nonaccrual status \| Contracts	0		0
Agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment of loans past due	$ 7
Number of loans in nonaccrual status \| Contracts	0		0
Agricultural \| Maximum
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded investment of loans past due			$ 1
Residential
Financing Receivable, Recorded Investment, Past Due [Line Items]
Estimated fair value	$ 2,700		2,300
Recorded investment of loans past due	38		36
Recorded investment of loans in nonaccrual status	38		36,000
Mortgage Loans
Financing Receivable, Recorded Investment, Past Due [Line Items]
Significant purchases	477	$ 100
Mortgage Loans \| Agricultural
Financing Receivable, Recorded Investment, Past Due [Line Items]
Estimated fair value	$ 3,100		$ 2,900