Investments (Details) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Available for Sale Securities
Total OTTI for AFS securities backed by pools of residential and commercial mortgages	$ 103,000,000	$ 135,000,000
OTTI for AFS securities backed by pools of residential and commercial mortgages recognized in OCI	(45,000,000)	(15,000,000)
OTTI for AFS securities backed by pools of residential and commercial mortgages recognized in net income (loss)	148,000,000	150,000,000
Decrease in gross AFS securities unrealized losses	594,000,000
Largest mortgage loan concentration in geographic region	32.00%	32.00%
Financing Receivable Allowance For Credit Losses [Roll Forward]
Balance as of beginning-of-year	31,000,000
Balance as of end-of-period	21,000,000	31,000,000
Alternative investments [Abstract]
Number of partnerships in alternative investment portfolio	98	96
Portion of the market adjustment for losses that relate to trading securities still held	53,000,000	118,000,000	93,000,000
Evaluation Of Credit Losses [Line Items]
Projected default rate on existing delinquencies on MBS (low end of range)	10.00%	10.00%
Projected default rate on existing delinquencies on MBS (high end of range)	100.00%	100.00%
Severity of second lien loans	100.00%	100.00%
Severity of first lien loans	30.00%	30.00%
Payables for collateral on investments
Percentage of the fair value of domestic securities obtained as collateral under securities lending agreements	102.00%	102.00%
Percentage of the fair value of foreign securities obtained as collateral under securities lending agreements	105.00%	105.00%
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements	95.00%	95.00%
Percentage of the fair value of TALF securities obtained as collateral under securities pledged for TALF	90.00%	90.00%
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI (low end of range)	105.00%
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI (high end of range)	115.00%
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI for mortgage loan (low end of range)	155.00%	85.00%
Percentage of the fair value of FHLBI securities obtained as collateral under securities pledged for FHLBI for mortgage loan (high end of range)	175.00%	95.00%
Investment commitments	536,000,000
Investment commitments for limited partnerships	226,000,000
Investment commitments for private placements	146,000,000	191,000,000
Investment commitments for mortgage loans on real estate	164,000,000	117,000,000
Federal Home Loan Mortgage Corporation [Member]
Concentration Risk [Line Items]
Fair value	3,800,000,000	5,000,000,000
Concentration risk, percentage	4.00%	5.00%
Fannie Mae [Member]
Concentration Risk [Line Items]
Fair value	2,200,000,000	2,600,000,000
Concentration risk, percentage	2.00%	3.00%
Cmo Industry [Member]
Concentration Risk [Line Items]
Fair value		5,600,000,000
Concentration risk, percentage		6.00%
Electric Industry [Member]
Concentration Risk [Line Items]
Fair value	8,700,000,000	7,700,000,000
Concentration risk, percentage	9.00%	8.00%
Banking Industry [Member]
Concentration Risk [Line Items]
Fair value	5,000,000,000
Concentration risk, percentage	5.00%
Corporate bonds [Member]
Evaluation Of Credit Losses [Line Items]
Percentage of fair value rated as investment grade	96.00%	96.00%
Amortized cost of portfolio rated below investment grade	3,000,000,000	2,600,000,000
Fair value of portfolio rated below investment grade	2,900,000,000	2,400,000,000
OTTI securities recognized in net income (loss), Recovery percentage of amortized cost	90.00%	98.00%
CDOs [Member]
Evaluation Of Credit Losses [Line Items]
Percentage of fair value rated as investment grade	93.00%	97.00%
Amortized cost of portfolio rated below investment grade	21,000,000	3,000,000
Fair value of portfolio rated below investment grade	$ 13,000,000	$ 3,000,000
OTTI securities recognized in net income (loss), Recovery percentage of amortized cost	90.00%	0.00%

Name:	lnc_AlternativeInvestmentsAbstract
Namespace Prefix:	lnc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amortized cost of portfolio rated below investment grade.

+ References

No definition available.

+ Details

Name:	lnc_AmortizedCostOfPortfolioRatedBelowInvestmentGrade
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the change in gross unrealized holding gain or loss on available-for-sale securities that has been included in accumulated other comprehensive income, a separate component of shareholders' equity, during the period.

+ References

No definition available.

+ Details

Name:	lnc_AvailableForSaleSecuritiesChangeInGrossUnrealizedHoldingGainLoss
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of the fair value of portfolio that was rated investment grade as of balance sheet date.

+ References

No definition available.

+ Details

Name:	lnc_AvailableForSaleSecuritiesFairValueDisclosurePercentInvestmentGrade
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Recovery as a percentage of amortized cost for securities with other than temporary impairment recorded in net income (loss).

+ References

No definition available.

+ Details

Name:	lnc_AvailableForSaleSecuritiesOtherThanTemporaryImpairmentRecoveryPercent
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the percentage of the fair value of Federal Home Loan Bank of Indianapolis securities obtained as collateral pledged for Federal Home Loan Bank of Indianapolis (high end of range).

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueFhlbiHighEndOfRangeAfs
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the percentage of the fair value of Mortgage loans obtained as collateral pledged for Federal Home Loan Bank of Indianapolis (high end of range).

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueFhlbiHighEndOfRangeMortgageLoan
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueFhlbiLowEndOfRangeFS
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the percentage of the fair value of Mortgage loans obtained as collateral pledged for Federal Home Loan Bank of Indianapolis (low end of range).

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueFhlbiLowEndOfRangeMortgageLoan
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the percentage of the fair value of securities obtained as collateral under reverse repurchase agreements

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueReverseRepurchaseAgreements
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the percentage of the fair value of domestic securities obtained as collateral under securities lending agreements

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueSecuritiesLendingAgreementsDomestic
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the percentage of the fair value of foreign securities obtained as collateral under securities lending agreements

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueSecuritiesLendingAgreementsForeign
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the average percentage of the fair value of Term Asset-Backed Securities Loan Facility securities obtained as collateral pledged for Term Asset-Backed Securities Loan Facility.

+ References

No definition available.

+ Details

Name:	lnc_CollateralObtainedPercentOfFairValueTalf
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	lnc_EvaluationOfCreditLossesLineItems
Namespace Prefix:	lnc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of portfolio rated below investment grade.

+ References

No definition available.

+ Details

Name:	lnc_FairValueOfPortfolioRatedBelowInvestmentGrade
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents total investment commitments as of the balance sheet date for fixed maturity available-for-sale securities, limited partnerships, real estate and mortgage loans on real estate.

+ References

No definition available.

+ Details

Name:	lnc_InvestmentCommitments
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This item represents investment commitments as of the balance sheet date for limited partnerships.

+ References

No definition available.

+ Details

Name:	lnc_InvestmentCommitmentsLimitedPartnerships
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This item represents investment commitments as of the balance sheet date for private placements.

+ References

No definition available.

+ Details

Name:	lnc_InvestmentCommitmentsLimitedPrivatePlacements
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This item represents investment commitments as of the balance sheet date for mortgage loans.

+ References

No definition available.

+ Details

Name:	lnc_InvestmentCommitmentsMortgageLoans
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Largest concentration percentage of mortgage loans on commercial real estate throughout the U.S.

+ References

No definition available.

+ Details

Name:	lnc_LargestMortgageLoanConcentrationInGeographicRegion
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of partnerships represented in alternative investment portfolio.

+ References

No definition available.

+ Details

Name:	lnc_NumberOfPartnershipsInAlternativeInvestmentPortfolio
Namespace Prefix:	lnc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Total other-than-temporary impairment for available-for-sale securities backed by pools of residential and commercial mortgages recognized during the reporting period.

+ References

No definition available.

+ Details

Name:	lnc_OtherThanTemporaryImpairmentForAfsSecuritiesBackedByPoolsOfMortgages
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Other-than-temporary impairment for available-for-sale securities backed by pools of residential and commercial mortgages relating to credit losses and recognized in net income (loss) during the reporting period.

+ References

No definition available.

+ Details

Name:	lnc_OtherThanTemporaryImpairmentForAfsSecuritiesBackedByPoolsOfMortgagesRealized
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Other-than-temporary impairment for available-for-sale securities backed by pools of residential and commercial mortgages relating to factors other than credit losses and recognized in other comprehensive income during the reporting period.

+ References

No definition available.

+ Details

Name:	lnc_OtherThanTemporaryImpairmentForAfsSecuritiesBackedByPoolsOfMortgagesUnrealized
Namespace Prefix:	lnc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This item represents the default rate (as a percentage) of the underlying assets in the security that was considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are other than temporarily impaired and the amount of such impairment determined to be related to credit loss recognized in earnings (high end of range).

+ References

No definition available.

+ Details

Name:	lnc_ProjectedDefaultRateOnExistingDeliquenciesPercentHighEndOfRange
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

+ References

No definition available.

+ Details

Name:	lnc_ProjectedDefaultRateOnExistingDeliquenciesPercentLowEndOfRange
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the loss severity as a percentage of first lien loans that was considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are other than temporarily impaired and the amount of such impairment determined to be related to credit loss recognized in earnings.

+ References

No definition available.

+ Details

Name:	lnc_SeverityOfFirstLienLoansAssumedMimimumPercent
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents the loss severity as a percentage of defaulted second lien loans that was considered as one of the potential factors in reaching a conclusion that the available-for-sale investments are other than temporarily impaired and the amount of such impairment determined to be related to credit loss recognized in earnings.

+ References

No definition available.

+ Details

Name:	lnc_SeverityOfSecondLienDefaultedLoans
Namespace Prefix:	lnc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 60

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488

+ Details

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

- Details

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

- Details

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

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13537-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13531-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details

Name:	us-gaap_ConcentrationRiskPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

This item represents disclosure of all significant concentrations of credit risk or market risk arising from the subject financial instrument (as defined), whether from an individual counterparty or groups of counterparties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Available-for-Sale Securities

-URI http://asc.fasb.org/extlink&oid=6505594

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15A

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15C

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6379932&loc=d3e22054-111558

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 1

-Subparagraph a, f, g

+ Details

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

- Details

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

- Details

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

- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of trading securities held at each balance sheet date, that was included in earnings for the period. Trading securities are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) and the change in net unrealized holding gain (loss) is included in earnings for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(c))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Trading Securities

-URI http://asc.fasb.org/extlink&oid=6526789

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 21

-Subparagraph e

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6956420&loc=d3e24584-111560

+ Details

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