Reinsurance (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Ceded Credit Risk [Line Items]
Percent of mortality risk reinsured on newly issued non-term life insurance contracts	25.00%
Maximum retention per single insured life on fixed and VUL insurance contracts	$ 20
Reserves associated with modified coinsurance reinsurance arrangements	676
Reinsurance receivable	5,700us-gaap_ReinsuranceReceivablesCaseBasis	6,000us-gaap_ReinsuranceReceivablesCaseBasis
Policy loans	2,670us-gaap_LoansInsurancePolicy	2,677us-gaap_LoansInsurancePolicy
Liabilities for funds withheld	764	867
Proceeds From Reinsurance Recapture	422lnc_ProceedsFromReinsuranceRecapture
Realized Gain Loss		(135)lnc_RealizedGainLoss	74lnc_RealizedGainLoss
Current Period Increase In Reserves	180lnc_CurrentPeriodIncreaseInReserves
Swiss Re [Member]
Ceded Credit Risk [Line Items]
Reinsurance receivable	2,500	2,600
Trust funded by Swiss Re to support reinsurance receivable	2,600
Liabilities for funds withheld	764
Liabilities for reinsurance related embedded derivatives	128
Amortization period (in years) of deferred gain on business sold to Swiss Re	15 years
Amount of amortization, after-tax, of deferred gain on business sold to Swiss Re	48	48	48
Reinsurance Recaptured [Member]
Ceded Credit Risk [Line Items]
Proceeds From Reinsurance Recapture	500
Reimbursement for prepaid reinsurance premiums	78
Realized Gain Loss	57
Current Period Increase In Reserves	226
Reduction of DAC	$ (123)

Amount, after-tax, of deferred gain on business sold through reinsurance amortized into income during the period.

No definition available.

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- Definition

Period (in years) over which the deferred gain related to indemnity reinsurance transactions is being amortized into income, at the rate that earnings on the reinsured business are expected to emerge.

+ References

No definition available.

+ Details

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- Definition

The current year increase in reserves.

+ References

No definition available.

+ Details

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- Definition

Maximum amount retained per single insured life issued on fixed and VUL insurance contracts.

+ References

No definition available.

+ Details

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- Definition

Disclosure of the percentage of mortality risk that is reinsured on newly issued non-term life insurance contracts.

+ References

No definition available.

+ Details

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- Definition

Operating cash inflow due to the recapture of several yearly renewable term reinsurance treaties that were originally ceded to a reinsurer.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting, losses recognized for other than temporary impairments (OTTI) of the subject investments, derivatives and embedded derivatives gains and losses and gains and losses from reinsurance embedded derivatives.

+ References

No definition available.

+ Details

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- Definition

Reimbursement for prepaid reinsurance premiums related to the recaptured treaties.

+ References

No definition available.

+ Details

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- Definition

Embedded derivatives within certain modified coinsurance and coinsurance with funds withheld reinsurance arrangements related to the withheld assets of the related funds.

+ References

No definition available.

+ Details

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- 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

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- Definition

Funds held in trust by the reinsurer to support the sale of the Entity's reinsurance business through an indemnity reinsurance agreement.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount of funds held as security for payments to be received under reinsurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.13(c))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph c

-Article 7

+ Details

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- Definition

The increase (decrease) during the reporting period in the balance sheet value of capitalized sales costs that are associated with acquiring a new insurance customers.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(7))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(e))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Subparagraph e

-Article 7

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- Definition

The sum for all reinsurance arrangements of the known and estimated amount recoverable as of the balance sheet date from a given reinsurer for claims paid or incurred by the ceding insurer and associated claims settlement expenses for each reinsurance arrangement (or, the sum of all cases determined individually, probably applying different assumptions to each arrangement).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21412-158489

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21409-158489

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.6)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 6

-Article 7

+ Details

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