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Derivative Instruments - Summary of Notional for VIE Derivatives Outstanding (Detail) - Variable Interest Entity, Primary Beneficiary [Member] - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
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Interest Rate Swap [Member] |  |
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items] |  |
Derivative products, Notional Amount | $ 1,427,299 | $ 1,399,532
Interest Rate Swaps-Pay-Fixed/Receive-Variable [Member] |  |
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items] |  |
Derivative products, Notional Amount | 1,189,113 | 1,176,748
Currency Swaps [Member] |  |
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items] |  |
Derivative products, Notional Amount | 344,714 | 344,992
Other Credit Derivatives [Member] |  |
Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items] |  |
Derivative products, Notional Amount | $ 10,457 | $ 10,254

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- Definition Schedule Of Loans And Allowance For Loan By Class Individually And Collectively Evaluated For Impairment [Line Items] + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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