Financing Receivables - General Credit Quality Information - Commercial Mortgage Loans - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Commercial Loans \| Commercial mortgage loans
Financing Receivables
Loans	$ 1,837	$ 1,832
Commercial Loans \| Commercial mortgage loans \| Past due
Financing Receivables
Loans	$ 0	$ 0
Total commercial mortgage loans \| Credit concentration risk \| Commercial Loans \| Commercial mortgage loans
Financing Receivables
Percentage of total	100.00%	100.00%
Total commercial mortgage loans \| Credit concentration risk \| Highest credit risk rating
Financing Receivables
Percentage of total	1.00%	1.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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