Name:	cik0000726865_PresentValueOfFutureInsuranceProfitsAdditionDispositionFromAcquisition
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Total amount of additions in present value of future profits asset from sources other than acquisitions of insurance entities during the income statement period.

No definition available.

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The amount of other amortization of the present value of future profits asset during the period.

No definition available.

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

Rate of interest used in determination of present value of future profits on insurance contract acquired in business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section S99
-Paragraph 2
-Subparagraph (2)
-URI https://asc.fasb.org/extlink&oid=122135039&loc=d3e569990-122904

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Data Type:	xbrli:stringItemType
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- References

No definition available.

Name:	us-gaap_PresentValueOfFutureInsuranceProfitsAmortizationExpenseAbstract
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Amount of amortization expense for present value of future profits of insurance contract acquired in business combination from accrued interest on unamortized balance.

No definition available.

Name:	us-gaap_PresentValueOfFutureInsuranceProfitsAmortizationExpenseAccruedInterest
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of amortization expense (reversal of amortization expense) for future profits of insurance contract acquired in business combination from assumption change.

No definition available.

Name:	us-gaap_PresentValueOfFutureInsuranceProfitsAmortizationExpenseAssumptionChange
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of amortization expense (reversal of amortization expense) for future profits of insurance contract acquired in business combination from realized investment gain (loss).

No definition available.

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

Amount of unrealized investment gain (loss) which decreases (increases) present value of future profits of insurance contract acquired in business combination.

No definition available.

Name:	us-gaap_PresentValueOfFutureInsuranceProfitsUnrealizedGainLossOnInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount, after accumulated amortization, of present value of future profits of insurance contract acquired in business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section S99
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=122135039&loc=d3e569990-122904

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 210.7-03.10)
-URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910