Outstanding Insurance Exposure Outstanding Insurance Exposure - Schedule of Non-Financial Guaranty Exposure (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Schedule of Insured Financial Obligations [Line Items]
Residual value insurance policies exposure downgraded	$ 1,484	$ 1,444
Net Exposure	1,178	1,141
Life Insurance Transaction [Member]
Schedule of Insured Financial Obligations [Line Items]
Residual value insurance policies exposure downgraded	1,091	1,046
Net Exposure	940	898
Aircraft residual value insurance policies [Member]
Schedule of Insured Financial Obligations [Line Items]
Residual value insurance policies exposure downgraded	393	398
Net Exposure	$ 238	$ 243