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

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

- References

No definition available.

+ Details

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

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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

- 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

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

- 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

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

- Details

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

Investments (Mortgage Loans - Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($) Contracts	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) Contracts	Sep. 30, 2017 USD ($) Contracts	Dec. 31, 2017 USD ($) Contracts
Financing Receivable, Additional Disclosures [Abstract]
Financing Receivable, Significant Purchases \| $	$ 816	$ 32	$ 1,400	$ 339
Financing Receivable, Recorded Investment, Aging [Abstract]
Percentage of Mortgage Loans Classified as Performing	99.00%		99.00%		99.00%
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| Contracts			0	0
Residential
Financing Receivable, Additional Disclosures [Abstract]
Estimated fair value of mortgage loans held-for-investment \| $	$ 1,800		$ 1,800		$ 1,200
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing Receivable, Recorded Investment,Past Due \| $	32		32		32
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest \| $	32		32		32
Agricultural
Financing Receivable, Additional Disclosures [Abstract]
Estimated fair value of mortgage loans held-for-investment \| $	$ 2,700		$ 2,700		$ 2,200
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing Receivable Number of Contract of Recorded Investment Past Due \| Contracts	0		0		0
Loans and Leases Receivable, Number of Contract, Nonperforming, Nonaccrual of Interest \| Contracts	0		0		0
Commercial
Financing Receivable, Recorded Investment, Aging [Abstract]
Financing Receivable Number of Contract of Recorded Investment Past Due \| Contracts	0		0		0
Loans and Leases Receivable, Number of Contract, Nonperforming, Nonaccrual of Interest \| Contracts	0		0		0