Investments (Schedule Of Increase (Decrease) In Payables For Collateral On Investments) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Increase (decrease) in payables for collateral on investments
Collateral payable for derivative investments	$ 246	$ 2,555
Securities pledged under securities lending agreements	29	47
Investments pledged for FHLBI	1,100	750
Total increase (decrease) in payables for collateral on investments	$ 1,375	$ 3,352

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.

No definition available.

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