Derivative Financial Instruments - Additional Information (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Derivative [Line Items]
Percentage of periodic changes in fair value qualifies for hedge accounting treatment (in percent)	100.00%
Interest Income
Derivative [Line Items]
Reclassified interest income (expense)	$ 5,800
Interest Expense
Derivative [Line Items]
Reclassified interest income (expense)	26,300
Interest rate swaps on borrowings \| Cash flow hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	150,000	$ 150,000
Interest rate swaps on borrowings \| Fair value hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	700,000	300,000
Interest rate collars and floors on loan pools \| Cash flow hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	1,500,000	1,900,000
Interest rate swaps on investment securities \| Fair value hedges \| Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	998,107	909,957
Interest rate lock commitments \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	42,492	21,401
Forward mortgage loan contracts \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	54,730	30,330
Counterparty interest rate swaps \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	5,775,634	5,220,363
Customer interest rate swaps \| Not Designated as Hedging Instrument
Derivative [Line Items]
Notional amount	$ 5,775,638	$ 5,220,363

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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