Fair Value of Financial Instruments - Fair Value Measured on a Recurring Basis Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	$ (5,693)	$ (5,766)	$ (6,472)	$ (4,458)
Items Included in Net Income	(1,830)	(29)	(2,328)	(1,511)
Gains (Losses) in OCI and Other	40	98	57	87
Issuances, Sales, Maturities, Settlements, Calls, Net	504	336	1,571	749
Transfers Into or Out of Level 3, Net	(191)	(190)	2	(418)
Ending Fair Value	(7,170)	(5,551)	(7,170)	(5,551)
Corporate bonds \| Fixed maturity AFS securities, at fair value
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	3,076	2,581	2,865	2,497
Items Included in Net Income	(6)	(1)	(43)	1
Gains (Losses) in OCI and Other	6	43	12	25
Issuances, Sales, Maturities, Settlements, Calls, Net	169	50	300	264
Transfers Into or Out of Level 3, Net	(52)	(7)	59	(121)
Ending Fair Value	3,193	2,666	3,193	2,666
State and municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value				5
Items Included in Net Income				0
Gains (Losses) in OCI and Other				0
Issuances, Sales, Maturities, Settlements, Calls, Net				0
Transfers Into or Out of Level 3, Net				(5)
Ending Fair Value		0		0
RMBS \| Fixed maturity AFS securities, at fair value
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	79	18	12	13
Items Included in Net Income	0	0	0	0
Gains (Losses) in OCI and Other	0	0	0	(1)
Issuances, Sales, Maturities, Settlements, Calls, Net	0	0	74	6
Transfers Into or Out of Level 3, Net	(67)	(5)	(74)	(5)
Ending Fair Value	12	13	12	13
CMBS \| Fixed maturity AFS securities, at fair value
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	41	23	8	8
Items Included in Net Income	0	0	0	0
Gains (Losses) in OCI and Other	1	0	1	0
Issuances, Sales, Maturities, Settlements, Calls, Net	19	14	59	29
Transfers Into or Out of Level 3, Net	0	(16)	(7)	(16)
Ending Fair Value	61	21	61	21
ABS \| Fixed maturity AFS securities, at fair value
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	3,000	1,997	2,099	1,484
Items Included in Net Income	0	0	(21)	0
Gains (Losses) in OCI and Other	34	50	41	55
Issuances, Sales, Maturities, Settlements, Calls, Net	427	232	1,324	798
Transfers Into or Out of Level 3, Net	(72)	(178)	(54)	(236)
Ending Fair Value	3,389	2,101	3,389	2,101
Hybrid and redeemable preferred securities \| Fixed maturity AFS securities, at fair value
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	92	50	73	48
Items Included in Net Income	0	0	0	0
Gains (Losses) in OCI and Other	0	1	0	3
Issuances, Sales, Maturities, Settlements, Calls, Net	0	16	19	16
Transfers Into or Out of Level 3, Net	0	10	0	10
Ending Fair Value	92	77	92	77
Trading securities
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	296	273	265	284
Items Included in Net Income	3	7	7	7
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	4	(6)	7	(17)
Transfers Into or Out of Level 3, Net	0	0	24	0
Ending Fair Value	303	274	303	274
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	83	38	34	42
Items Included in Net Income	(1)	0	(9)	(3)
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	4	1	7	0
Transfers Into or Out of Level 3, Net	0	(4)	54	(4)
Ending Fair Value	86	35	86	35
Mortgage loans on real estate
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	232	258	232	288
Items Included in Net Income	(1)	2	(3)	6
Gains (Losses) in OCI and Other	(1)	4	3	5
Issuances, Sales, Maturities, Settlements, Calls, Net	0	(1)	(2)	(36)
Transfers Into or Out of Level 3, Net	0	0	0	0
Ending Fair Value	230	263	230	263
Other investments
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	24	0	23	0
Items Included in Net Income	0	0	0	0
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	(16)	10	(15)	10
Transfers Into or Out of Level 3, Net	0	10	0	10
Ending Fair Value	8	20	8	20
Derivative investments
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value		(8)	(136)	36
Items Included in Net Income		6	25	11
Gains (Losses) in OCI and Other		0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net		1	0	3
Transfers Into or Out of Level 3, Net		0	0	(51)
Ending Fair Value	(111)	(1)	(111)	(1)
Ceded MRBs \| Other Assets
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	2	2	2	2
Items Included in Net Income	0	0	0	0
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	0	0	0	0
Transfers Into or Out of Level 3, Net	0	0	0	0
Ending Fair Value	2	2	2	2
Ceded MRBs \| Other Liabilities
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	(341)	(344)	(381)	(239)
Items Included in Net Income	(8)	3	32	(102)
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	0	0	0	0
Transfers Into or Out of Level 3, Net	0	0	0	0
Ending Fair Value	(349)	(341)	(349)	(341)
Indexed annuity ceded embedded derivatives \| Other Assets
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	1,236	967	1,115	940
Items Included in Net Income	64	191	112	238
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	33	(26)	106	(46)
Transfers Into or Out of Level 3, Net	0	0	0	0
Ending Fair Value	1,333	1,132	1,333	1,132
RILA, fixed indexed annuity and IUL contracts \| Policyholder Account Balances
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	(13,089)	(11,417)	(12,449)	(9,077)
Items Included in Net Income	(1,693)	(898)	(2,161)	(2,915)
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	(136)	45	(308)	(278)
Transfers Into or Out of Level 3, Net	0	0	0	0
Ending Fair Value	(14,918)	(12,270)	(14,918)	(12,270)
Reinsurance-related embedded derivatives
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	(309)	(204)	(234)	(789)
Items Included in Net Income	(192)	661	(267)	1,246
Gains (Losses) in OCI and Other	0	0	0	0
Issuances, Sales, Maturities, Settlements, Calls, Net	0	0	0	0
Transfers Into or Out of Level 3, Net	0	0	0	0
Ending Fair Value	(501)	$ 457	(501)	$ 457
Derivative liabilities
Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract]
Beginning Fair Value	(115)
Items Included in Net Income	4
Gains (Losses) in OCI and Other	0
Issuances, Sales, Maturities, Settlements, Calls, Net	0
Transfers Into or Out of Level 3, Net	0
Ending Fair Value	$ (111)		$ (111)

LINCOLN NATIONAL CORP 10-Q