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Investments - Schedule of Payment Status of Mortgage Loans (Details) - Mortgage loans - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Schedule of Available for Sale Securities
Amortized cost before allowance	$ 889
Allowance	(10)
Total mortgage loans	879
Commercial
Schedule of Available for Sale Securities
Amortized cost before allowance	628	$ 735
Allowance	(9)
Total mortgage loans	619
Residential
Schedule of Available for Sale Securities
Amortized cost before allowance	261
Allowance	(1)
Total mortgage loans	260
Less than 90 days past due
Schedule of Available for Sale Securities
Amortized cost before allowance	2
Less than 90 days past due \| Commercial
Schedule of Available for Sale Securities
Amortized cost before allowance	0
Less than 90 days past due \| Residential
Schedule of Available for Sale Securities
Amortized cost before allowance	2
90 days or greater past due
Schedule of Available for Sale Securities
Amortized cost before allowance	2
90 days or greater past due \| Commercial
Schedule of Available for Sale Securities
Amortized cost before allowance	0
90 days or greater past due \| Residential
Schedule of Available for Sale Securities
Amortized cost before allowance	2
Total past due before allowance
Schedule of Available for Sale Securities
Amortized cost before allowance	4
Total past due before allowance \| Commercial
Schedule of Available for Sale Securities
Amortized cost before allowance	0
Total past due before allowance \| Residential
Schedule of Available for Sale Securities
Amortized cost before allowance	4
Current before allowance
Schedule of Available for Sale Securities
Amortized cost before allowance	885
Current before allowance \| Commercial
Schedule of Available for Sale Securities
Amortized cost before allowance	628
Current before allowance \| Residential
Schedule of Available for Sale Securities
Amortized cost before allowance	$ 257