Fair Value of Financial Instruments (Components Of The Transfers In And Out Of Level 3) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3		$ 179	$ 24	$ 326
Transfers Out of Level 3	$ 762	(115)	660	(297)
Total	762	64	684	29
Corporate Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3		135	10	254
Transfers Out of Level 3	(1)	(85)	(39)	(162)
Total	(1)	50	(29)	92
RMBS [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3		1		1
Transfers Out of Level 3				(10)
Total		1		(9)
ABS [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3		15		20
Transfers Out of Level 3	(162)	(28)	(220)	(123)
Total	(162)	(13)	(220)	(103)
Foreign Government Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Out of Level 3	(37)		(37)
Total	(37)		(37)
Hybrid And Redeemable Preferred Securities [Member] \| Fixed Maturity AFS Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3		18		18
Total		18		18
Trading Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Into Level 3		10	14	33
Transfers Out of Level 3	(23)	(2)	(29)	(2)
Total	(23)	$ 8	(15)	$ 31
Derivative Investments [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Out of Level 3	(2,658)		(2,658)
Total	(2,658)		(2,658)
Indexed Annuity And IUL Contracts [Member] \| Future Contract Benefits [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Out of Level 3	4,170		4,170
Total	4,170		4,170
GLB Embedded Derivatives [Member] \| Other Assets [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net [Abstract]
Transfers Out of Level 3	(527)		(527)
Total	$ (527)		$ (527)

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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

- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CorporateBondSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_FixedMaturitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ResidentialMortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ForeignGovernmentDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=lnc_HybridAndRedeemablePreferredSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_TradingAssetsExcludingDebtAndEquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_DerivativeFinancialInstrumentsAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=lnc_IndexedAnnuityContractsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=lnc_FutureContractBenefitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=lnc_GuaranteedLivingBenefitsEmbeddedDerivativeReservesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_OtherAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: