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Deposits (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Deposits [Abstract]
Public funds deposits included in deposits	$ 1,900.0		$ 1,900.0		$ 3,100.0
Interest-bearing domestic deposit, brokered	4,500.0		4,500.0		$ 5,200.0
Noninterest Expense Commission Expense	$ 15.3	$ 15.3	$ 43.0	$ 42.3

X

- Definition

Public funds deposits included in deposits.

+ References

No definition available.

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- References

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X

- Definition

Amount of interest-bearing domestic third-party deposits placed by or through the assistance of a deposit broker, also known as brokered deposit liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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- Definition

Amount of fees incurred for commissions on mutual funds and insurance products.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(14))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

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