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Outstanding Exposure - Schedule of Non-Financial Guaranty Exposure (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Life insurance transactions
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	$ 1,325	$ 1,314
Net Exposure	1,003	986
Life insurance transactions | Maximum
Schedule of Insured Financial Obligations [Line Items]
Net Exposure	1,100
Aircraft residual value insurance policies
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	355	355
Net Exposure	200	200
Other guaranties
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	2,090	228
Net Exposure	$ 2,090	$ 228

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[Line Items] for Schedule of Insured Financial Obligations [Table]

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Specialty Business, Gross Par

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