Federal Income Taxes (Federal Income Tax Asset (Liability)) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Federal income tax asset (liability) [Abstract]
Current	$ 353	$ 382
Deferred	824	(3,122)
Total federal income tax asset (liability)	$ 1,177	$ (2,740)

Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes, net of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due.

No definition available.

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Namespace Prefix:	cik0000726865_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant