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Derivative Instruments and Hedging Activities - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Derivative [Line Items] |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax | $ 0.3 | $ (4.4) |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax | (1.0) | (3.5) |
Derivative Notional Amount Terminated | 300.0 |  | $ 550.0
Gain (Loss) on Hedging Activity |  |  | $ 0.2
Derivative Instruments and Hedges, Noncurrent | 300.0 |  |
Not Designated as Hedging Instrument |  |  |
Derivative [Line Items] |  |  |
Amount of net fee income recognized in other noninterest income | 0.0 | 0.0 |
Amount of net gains recognized in mortgage banking revenues | 0.0 | 0.0 |
Interest Rate Swap |  |  |
Derivative [Line Items] |  |  |
Derivative Instruments and Hedges, Assets | 850.0 |  |
Interest Rate Swap | Cash Flow Hedging [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax | (1.0) | $ 17.4 |
Interest Rate Collars |  |  |
Derivative [Line Items] |  |  |
Derivative Instruments and Hedges, Assets | $ 300.0 |  |

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- Definition Carrying amount as of the balance sheet date of the asset arising from derivative instruments and hedging activities, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(8)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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