Long-Term Debt and Other Borrowed Funds - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Other Short-term Borrowings	$ 960.0	$ 1,567.5
5.01% fixed rate borrowings in tenors up to one-month
Fixed-to-floating rate (percent)	4.53%	4.77%
Notes Payable to FHLB \| Subsidiaries \| Federal Home Loan Bank Advances
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	$ 4,958.7
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available	$ 5,922.6

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

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-Topic 210
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-Name Accounting Standards Codification
-Section S99
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-Name Accounting Standards Codification
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Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

+ Details

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Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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