Amount of allowance for credit loss on reinsurance recoverable and deposit assets.

No definition available.

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Namespace Prefix:	cik0000726865_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of reserves associated with modified coinsurance reinsurance arrangements for portions of the Company's deferred annuity business.

+ References

No definition available.

+ Details

Name:	cik0000726865_ReservesAssociatedWithModifiedCoinsurance
Namespace Prefix:	cik0000726865_
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

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

- Definition

The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

+ 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 210.5-02.8,17)
-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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Details

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

- Details

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Namespace Prefix:
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Reinsurance (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Ceded Credit Risk [Line Items]
Reinsurance ACL and deposit assets		$ 190
Athene Holding Ltd. [Member]
Ceded Credit Risk [Line Items]
Deposit assets	$ 5,900		$ 6,600
Reserves associated with modified coinsurance reinsurance arrangements	6,303		$ 6,897
Letter of credit	175
Athene Holding Ltd. [Member] \| Ceded Credit Risk, Secured [Member]
Ceded Credit Risk [Line Items]
Reserves associated with modified coinsurance reinsurance arrangements	$ 186