Summary of Significant Accounting Policies - Variable Interest Entities (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Variable Interest Entity [Line Items]
Consolidated VIEs, assets	$ 22,284.1	$ 21,176.0
Consolidated VIEs, liabilities	16,554.7	15,391.5
Investments in CLOs	205.1
Investment fund	346.5
Consolidated VIEs
Variable Interest Entity [Line Items]
Consolidated VIEs, assets	9,700.0	7,800.0
Consolidated VIEs, liabilities	$ 9,000.0	$ 6,900.0

Amount of asset recognized for present right to economic benefit.

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+ Details

- Definition

Amount of liability recognized for present obligation requiring transfer or otherwise providing economic benefit to others.

+ References

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+ Details

- 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.

+ References + Details