Derivative Financial Instruments - Additional Information (Details) - USD ($)	Sep. 30, 2024	Dec. 31, 2023
Derivative [Line Items]
Percentage of periodic changes in fair value qualifies for hedge accounting treatment (in percent)	100.00%
Interest Income
Derivative [Line Items]
Hedge gain to be reclassified during next twelve months, net	$ 6,100,000
Interest Expense
Derivative [Line Items]
Hedge gain to be reclassified during next twelve months, net	15,800,000
Interest rate swaps on borrowings \| Cash flow hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	150,000,000	$ 150,000,000
Interest rate swaps on borrowings \| Fair value hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	1,100,000,000	900,000,000.0
Interest rate swaps, collars, and floors on loan pools \| Cash flow hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	1,800,000,000	1,600,000,000
Interest rate swaps on investment securities \| Fair value hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	998,107,000	998,107,000
Interest rate lock commitments \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	110,582,000	25,151,000
Forward mortgage loan contracts \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	154,287,000	39,529,000
Customer and offsetting counterparty derivative instruments \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	$ 6,200,000,000	$ 6,000,000,000.0

Percentage of periodic changes in fair value qualifies for hedge accounting.

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- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480870/815-30-50-1

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