Variable Interest Entities (Details) $ in Billions	Sep. 30, 2023 USD ($) entity	Dec. 31, 2022 USD ($) entity
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Number of VIEs | entity	0	0
Variable Interest Entity, Not Primary Beneficiary | Securities limited partnerships and real estate limited partnerships
Variable Interest Entity [Line Items]
Maximum exposure to loss, variable interest entities	$ 5.1	$ 4.8
Variable Interest Entity, Not Primary Beneficiary | Real estate joint ventures
Variable Interest Entity [Line Items]
Maximum exposure to loss, variable interest entities	$ 0.9	$ 0.6