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Derivative Financial Instruments (Schedule of Notional Amounts and Estimated Fair Values of Interest Rate Derivative Contracts Outstanding) (Detail) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Designated as Hedging Instrument [Member] | Financial Institution Counterparties Loan Lease Interest Rate Swaps Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Notional Amount | $ 0 | $ 2,545
Estimated Fair Value | 0 | 6
Designated as Hedging Instrument [Member] | Financial Institution Counterparties Loan Lease Interest Rate Swaps Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Notional Amount | 3,724 | 6,000
Estimated Fair Value | (134) | (138)
Not Designated as Hedging Instrument [Member] | Financial Institution Counterparties Loan Lease Interest Rate Swaps Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Notional Amount | 0 | 122,788
Estimated Fair Value | 0 | 67
Not Designated as Hedging Instrument [Member] | Financial Institution Counterparties Loan Lease Interest Rate Swaps Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Notional Amount | 1,173,173 | 1,002,860
Estimated Fair Value | (33,812) | (19,483)
Not Designated as Hedging Instrument [Member] | Financial Institution Counterparties Loan Lease Interest Rate Caps Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Notional Amount | 356,601 | 107,835
Estimated Fair Value | 1,241 | 266
Not Designated as Hedging Instrument [Member] | Customer Counterparties Loan Lease Interest Rate Swaps Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Notional Amount | 1,173,173 | 1,002,860
Estimated Fair Value | 84,424 | 43,857
Not Designated as Hedging Instrument [Member] | Customer Counterparties Loan Lease Interest Rate Swaps Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Notional Amount | 0 | 122,788
Estimated Fair Value | 0 | (310)
Not Designated as Hedging Instrument [Member] | Customer Counterparties Loan Lease Interest Rate Caps Liabilities [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Liability, Notional Amount | 356,601 | 107,835
Estimated Fair Value | $ (1,241) | $ (266)

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- Definition Nominal or face amount used to calculate payments on the derivative asset. + References Reference 1: 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=121590274&loc=SL5579245-113959 Reference 2: 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=121590274&loc=SL5580258-113959 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: 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 + Details
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