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Derivative Financial Instruments - Additional Information (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
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Derivative [Line Items] |  |
Percentage of periodic changes in fair value qualifies for hedge accounting treatment | 100.00% |
Interest Income |  |
Derivative [Line Items] |  |
Reclassified interest income (expense) | $ 1,500 |
Interest Expense |  |
Derivative [Line Items] |  |
Reclassified interest income (expense) | 100 |
Interest rate swaps on borrowings | Cash flow hedges | Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | 150,000 | $ 325,000
Interest rate swaps on borrowings | Fair value hedges | Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | 377,500 | 379,000
Interest rate collars and floors on loan pools | Cash flow hedges | Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | 450,000 | 400,000
Interest rate swaps on investment securities | Fair value hedges | Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | 909,957 | 347,516
Interest rate lock commitments | Not Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | 188,963 | 224,719
Forward mortgage loan contracts | Not Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | 215,238 | 261,027
Counterparty interest rate swaps | Not Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | 2,384,213 | 2,008,149
Customer interest rate swaps | Not Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Notional amount | $ 2,384,213 | $ 2,008,149

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- Definition Percentage of periodic changes in fair value qualifies for hedge accounting. + References No definition available. + Details
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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 No definition available. + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959 + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994 + Details
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