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Investments in Qualified Affordable Housing Partnerships, Tax Credit and Other Investments, Net and Variable Interest Entities -Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2023 | Dec. 31, 2022
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Minimum compliance period for qualified affordable housing partnerships to fully utilize the tax credits (in years) |  | 15 years |
Rayliant Global Advisors Limited |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Equity method investment, ownership (percent) | 49.99% | 49.99% |
Payments to acquire equity method investments | $ 94.7 |  |
Equity method investment, difference between carrying amount and underlying equity | 100.7 | $ 100.7 |
Equity securities without readily determinable fair values | $ 110.9 | 110.9 |
Asset Acquisition, Contingent Consideration, Number of Shares | 349,138 |  |
Rayliant Global Advisors Limited | Performance-based RSUs | Minimum |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Shares based upon Rayliant’s achievement of specified financial performance conditions (as percentage) | 20.00% |  |
Rayliant Global Advisors Limited | Performance-based RSUs | Maximum |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Shares based upon Rayliant’s achievement of specified financial performance conditions (as percentage) | 200.00% |  |
Tax credit investments |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Equity securities | $ 23.6 | 23.6 | $ 24.0
Investments in Tax Credit and Other Investments and Other Assets |  |  |
Investments in Tax Credit and Other Investments, Net [Line Items] |  |  |
Equity securities without readily determinable fair values | $ 148.0 | $ 148.0 | $ 36.5

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