Investments (Schedule Of Increase (Decrease) In Payables For Collateral On Investments) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Increase (decrease) in payables for collateral on investments
Collateral payable held for derivative investments	$ 364	$ 638
Securities pledged under securities lending agreements	25	13
Securities pledged under reverse repurchase agreements	319	(325)
Securities pledged for TALF		(36)
Securities pledged for FHLBI	180	325
Total increase (decrease) in payables for collateral on investments	$ 888	$ 615

- Definition

The net change during the reporting period in the amount of cash that is received related to collateral payable held for derivative instruments.

+ References

No definition available.

+ Details

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- Definition

The net change during the reporting period in the amount of cash that is received related to securities pledged under reverse repurchase agreements

+ References

No definition available.

+ Details

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- Definition

The net change during the reporting period in the amount of cash that is received related to securities pledged under securities lending agreements.

+ References

No definition available.

+ Details

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- Definition

The net change during the reporting period in the amount of cash that is received related to securities pledged for Federal Home Loan Bank of Indianapolis.

+ References

No definition available.

+ Details

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- Definition

The net change during the reporting period in the amount of cash that is received related to securities pledged for Term Asset-Backed Securities Loan Facility.

+ References

No definition available.

+ Details

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- Definition

The increase (decrease) during the reporting period in the amount that is received as security when loaning securities.

+ References

No definition available.

+ Details

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

- References

No definition available.

+ Details

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