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 LNL)	$ 694	$ 616
Collateral Posted by LNL (Held by Counter-Party)	(116)	(66)
AA- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNL)	56	33
Collateral Posted by LNL (Held by Counter-Party)	(3)	(4)
A+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNL)	389	296
Collateral Posted by LNL (Held by Counter-Party)	(113)	(26)
A [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNL)	5	106
Collateral Posted by LNL (Held by Counter-Party)		(36)
A- [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNL)	244	4
Collateral Posted by LNL (Held by Counter-Party)
BBB+ [Member]
Credit Derivatives [Line Items]
Collateral Posted by Counter-Party (Held by LNL)		177
Collateral Posted by LNL (Held by Counter-Party)