Derivative Instruments (Schedule Of Collateral Amounts With Rights To Reclaim Or Obligation To Return Cash) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	$ 3,942	$ 1,387
Collateral Posted by LNC (Held by Counter-Party)	(1,489)	(557)
AA- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	521	441
Collateral Posted by LNC (Held by Counter-Party)	(599)	(167)
A+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	2,674	555
Collateral Posted by LNC (Held by Counter-Party)	(493)	(339)
A [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	35	36
Collateral Posted by LNC (Held by Counter-Party)
A- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	712	355
Collateral Posted by LNC (Held by Counter-Party)	(397)	(51)
BBB+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)
Collateral Posted by LNC (Held by Counter-Party)