Fair Value Measurements - Fair Value Option on Consolidated VIEs (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Mortgage loans \| VIE
Fair Value Option, Quantitative Disclosures
Fair value	$ 140.6
Aggregate contractual principal	140.6
Other loans \| VIE
Fair Value Option, Quantitative Disclosures
Fair value	129.0	$ 163.2
Aggregate contractual principal	139.9	167.1
Long-term debt \| VIE
Fair Value Option, Quantitative Disclosures
Fair value	21.8
Aggregate contractual principal	21.8
Other loans of consolidated VIEs
Fair Value Option, Quantitative Disclosures
Change in fair value pre-tax gain (loss) - instrument specific credit risk	(22.8)	(5.6)
Change in fair value pre-tax gain (loss)	(22.8)	(5.6)
Interest income	$ 31.0	$ 8.1

The amount change in fair value pre-tax loss - instrument specific credit risk.

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- Definition

The contractual principal amounts of assets for which the fair value option was elected.

+ References

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- Definition

The contractual principal amounts of liabilities for which the fair value option was elected.

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- Definition

The fair value of assets for which the fair value option was elected.

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- Definition

The fair value of liabilities of consolidated variable interest entities for which the fair value option was elected.

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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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