Outstanding Exposure - Schedule of Non-Financial Guaranty Exposure (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Insurance securitizations
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	$ 1,454	$ 1,370
Net Exposure	1,124	1,043
Insurance securitizations | Maximum
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	1,600
Net Exposure	1,300
Diversified real estate
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	1,509	1,569
Net Exposure	1,509	1,569
Pooled corporate obligations
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	694	488
Net Exposure	694	488
Aircraft residual value insurance
Schedule of Insured Financial Obligations [Line Items]
Gross Exposure	308	355
Net Exposure	$ 176	$ 200