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Derivatives and Hedging Activities - Impact of Fair Value Hedge Accounting on the Carrying Value of the Hedged Items (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2024
Derivatives, Fair Value [Line Items] |  |
Carrying value of hedged items | $ 7,287,540,000 | $ 7,095,344,000
Hedged Liability, Statement of Financial Position [Extensible Enumeration] | Net loans | Net loans
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items | $ 20,005,000 | $ (23,413,000)
Other assets |  |
Derivatives, Fair Value [Line Items] |  |
Notional amount | 1,981,554,000 | 4,530,941,000
Mortgage loan fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Portfolio layer method, amortized cost | 7,252,017,000 | 7,063,384,000
Portfolio layer method, cumulative adjustment, increase (decrease) | 21,476,000 | (21,080,000)
Amortized cost, designated in portfolio hedging relationship |  | 2,570,000,000
Hedged asset, discontinued | 300,000,000 |
Hedged asset, discontinued fair value | 1,232,211 |
Mortgage loan fair value hedges | Other assets |  |
Derivatives, Fair Value [Line Items] |  |
Notional amount | 0 | 2,570,000,000
Commercial loan fair value hedges |  |
Derivatives, Fair Value [Line Items] |  |
Carrying value of hedged items | 35,523,000 | 31,960,000
Cumulative gain (loss) fair value hedge adjustment included in carrying amount of hedged items | (1,471,000) | (2,333,000)
Commercial loan fair value hedges | Other assets |  |
Derivatives, Fair Value [Line Items] |  |
Notional amount | $ 37,042,000 | $ 34,341,000

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- Definition Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, remaining after discontinued hedge. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 181 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-181 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4EE -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4EE + Details
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