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Derivative Financial Instruments - Summary of Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
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Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Assets | $ 63,407 | $ 17,202
Liabilities | 0 | 1,988
Designated as Hedging Instrument | Cash flow hedges | Interest rate collars and floors on loan pools |  |
Derivative [Line Items] |  |
Notional | 400,000 | 400,000
Assets | 4,830 | 6,636
Liabilities | 0 | 0
Designated as Hedging Instrument | Cash flow hedges | Interest rate swaps on borrowings |  |
Derivative [Line Items] |  |
Notional | 150,000 | 325,000
Assets | 4,548 | 628
Liabilities | 0 | 1,816
Designated as Hedging Instrument | Fair value hedges | Interest rate swaps on borrowings |  |
Derivative [Line Items] |  |
Notional | 379,000 | 379,000
Assets | 7,218 | 8,793
Liabilities | 0 | 0
Designated as Hedging Instrument | Fair value hedges | Interest rate swaps on investment securities |  |
Derivative [Line Items] |  |
Notional | 884,957 | 347,516
Assets | 46,811 | 1,145
Liabilities | 0 | 172
Not Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Assets | 75,037 | 122,999
Liabilities | 23,700 | 16,199
Not Designated as Hedging Instrument | Interest rate lock commitments |  |
Derivative [Line Items] |  |
Notional | 237,439 | 224,719
Assets | 5,454 | 9,375
Liabilities | 0 | 0
Not Designated as Hedging Instrument | Forward mortgage loan contracts |  |
Derivative [Line Items] |  |
Notional | 273,710 | 261,027
Assets | 4,847 | 0
Liabilities | 0 | 2,335
Not Designated as Hedging Instrument | Customer interest rate swaps |  |
Derivative [Line Items] |  |
Notional | 2,098,087 | 2,008,149
Assets | 63,403 | 113,300
Liabilities | 14,715 | 133
Not Designated as Hedging Instrument | Counterparty interest rate swaps |  |
Derivative [Line Items] |  |
Notional | 2,098,087 | 2,008,149
Assets | 778 | 0
Liabilities | 8,602 | 13,543
Interest rate contracts net adjustment | 41,200 | 100,400
Not Designated as Hedging Instrument | Customer foreign currency forward contracts |  |
Derivative [Line Items] |  |
Notional | 22,849 | 9,990
Assets | 555 | 324
Liabilities | 0 | 0
Not Designated as Hedging Instrument | Counterparty foreign currency forward contracts |  |
Derivative [Line Items] |  |
Notional | 22,644 | 9,854
Assets | 0 | 0
Liabilities | $ 383 | $ 188

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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