v3.25.3

Future Contract Benefits - Summary of Changes in Present Values of LFPB (Group Protection) (Details) - Group Protection - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Present Value of Expected Future Policy Benefits
Balance as of beginning-of-year	$ 5,628	$ 5,689
Less: Effect of cumulative changes in discount rate assumptions			$ (550)	$ (490)
Beginning balance of original discount rate	6,178	6,179
Effect of changes in cash flow assumptions			(66)	(2)
Effect of actual variances from expected experience			$ (191)	$ (278)
Adjusted balance as of beginning-of-year	5,921	5,899
New incidence	1,176	1,236
Interest	148	138
Benefit payments	(1,080)	(1,125)
Ending balance at original discount rate	6,165	6,148
Effect of cumulative changes in discount rate assumptions	(371)	(375)
Balance as of end-of-period	5,794	5,773
Less: Reinsurance recoverables	4,213	4,153
Net balance as of end-of-period, net of reinsurance	$ 1,581	$ 1,620
Weighted-average duration of future policyholder benefit liability (years)	5 years	5 years

Amount, before tax, of accumulated other comprehensive income (loss) (AOCI) from (increase) decrease in expected future policy benefit component of liability for future policy benefit from change in discount rate.

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Amount, before tax, of accumulated other comprehensive income (loss) (AOCI) from increase (decrease) in expected net premium component of liability for future policy benefit from change in discount rate.

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Amount, after effect of reinsurance, of liability for future policy benefit.

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Amount of cumulative increase (decrease) in expected future policy benefit and expense component for liability of future policy benefit from cash flow assumption change for future cash flows.

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Amount of cumulative increase (decrease) in expected future policy benefit and expense component for liability of future policy benefit from effect of variance from cash flow assumption change for actual experience.

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Amount of interest expense for expected future policy benefit and expense component of liability for future policy benefit.

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Amount of increase in expected future policy benefit and expense component of liability for future policy benefit from contract issuance.

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Amount, before effect of reinsurance and current period update of cash flow assumption, of expected future policy benefit and expense component of liability for future policy benefit, discounted at original rate.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount, after allowance for credit loss, recoverable under reinsurance of liability for future policy benefit.

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Weighted-average duration of liability for future policy benefit, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of cash outflow to policyholder from benefit payment for expected future policy benefit and expense component of liability for future policy benefit.

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LINCOLN NATIONAL LIFE INSURANCE CO /IN/ 10-Q