Derivative Instruments (Schedule Of Collateral Amounts With Rights To Reclaim Or Obligation To Return Cash) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	$ 694	$ 636
Collateral Posted by LNC (Held by Counter-Party)	(285)	(155)
AA- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	56	33
Collateral Posted by LNC (Held by Counter-Party)	(3)	(3)
A+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	389	296
Collateral Posted by LNC (Held by Counter-Party)	(281)	(96)
A [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	5	106
Collateral Posted by LNC (Held by Counter-Party)		(56)
A- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	244	4
Collateral Posted by LNC (Held by Counter-Party)	(1)
BBB+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)		197
Collateral Posted by LNC (Held by Counter-Party)