Fair Value Measurements - Fair Value Option on Consolidated VIEs (Details) - VIE - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Mortgage loans
Fair Value Option, Quantitative Disclosures
Fair value			$ 140.6
Aggregate contractual principal			140.6
Other loans
Fair Value Option, Quantitative Disclosures
Fair value	$ 116.8		129.0
Aggregate contractual principal	123.1		139.9
Change in fair value pre-tax gain (loss) - instrument specific credit risk	1.6	$ (5.3)
Change in fair value pre-tax gain (loss)	1.6	(5.3)
Interest income	$ 4.2	$ 7.2
Long-term debt
Fair Value Option, Quantitative Disclosures
Fair value			21.8
Aggregate contractual principal			$ 21.8

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

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

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

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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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This item represents the estimated amount of gains or losses included in earnings during the period attributable to changes in instrument-specific credit risk arising from loans and other receivables held as assets.

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

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