Policyholder Account Balances - Narrative (Details) - FABN - The Lincoln National Life Insurance Company - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025	Dec. 31, 2024
Federal Home Loan Bank
Policyholder Account Balance [Line Items]
Long-term debt	$ 1,700	$ 1,500
Long-term debt, term	1 year
Sustainable Financing
Policyholder Account Balance [Line Items]
Debt instrument, face amount			$ 5,000
Long-term debt	$ 1,900	1,500
Sustainable Financing | Minimum
Policyholder Account Balance [Line Items]
Long-term debt, term	3 years
Sustainable Financing | Maximum
Policyholder Account Balance [Line Items]
Long-term debt, term	5 years
Secured Debt
Policyholder Account Balance [Line Items]
Debt instrument, face amount	$ 800	$ 800
Long-term debt, term	5 years