Derivative Instruments (Schedule Of Collateral Amounts With Rights To Reclaim Or Obligation To Return Cash) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	$ 1,139	$ 636
Collateral Posted by LNC (Held by Counter-Party)	(461)	(155)
AA- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	306	33
Collateral Posted by LNC (Held by Counter-Party)	(186)	(3)
A+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	466	296
Collateral Posted by LNC (Held by Counter-Party)	(212)	(96)
A [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	12	106
Collateral Posted by LNC (Held by Counter-Party)	(30)	(56)
A- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	18	4
Collateral Posted by LNC (Held by Counter-Party)
BBB+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNC)	337	197
Collateral Posted by LNC (Held by Counter-Party)	$ (33)