Related Party Transactions (Effects of Affiliated Reinsurance on Balance Sheets) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Assets:
Premiums, reinsurance and other receivables	$ 13,447	$ 13,113
Liabilities:
Policyholder account balances	40,459	39,330
Other Liabilities	4,607	3,455
Assumed
Assets:
Premiums, reinsurance and other receivables	20	21
Liabilities:
Policyholder account balances	381	386
Other policy-related balances	12	14
Other Liabilities	(38)	(38)
Ceded
Assets:
Premiums, reinsurance and other receivables	0	0
Liabilities:
Policyholder account balances	0	0
Other policy-related balances	0	0
Other Liabilities	$ 0	$ 0

Liability as of the balance sheet date to the policyholders for funds held that are returnable under the terms of insurance contracts that were not separately reported. Also includes unearned premiums.

No definition available.

+ Details

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

- References

No definition available.

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Balance Type:	na
Period Type:	duration

- References

No definition available.

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

- Definition

Amount of liabilities classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Definition

The liability as of the balance sheet date to the policyholders for deposits held under the terms of insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 30
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49168914&loc=d3e13951-158433

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.13(a)(3))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of all premiums and other types of receivables due from other persons or entities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.5)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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