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Derivative Financial Instruments (Narrative) (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Derivative [Line Items] |  |
Weighted-average strike rate for outstanding interest rate caps | 3.14% |
Approximate credit exposure related to swaps with bank customers | $ 47,100 |
Cash collateral on deposit with other financial institutions | 37,500 | $ 10,000
Interest Rate Swaps With Upstream Financial Institution Counterparties [Member] |  |
Derivative [Line Items] |  |
Approximate credit exposure related to swaps with bank customers | 16,100 |
Not Designated as Hedging Instrument [Member] | Financial Institution Counterparties Loan Lease Interest Rate Swaps Liabilities [Member] |  |
Derivative [Line Items] |  |
Estimated fair value of derivative contracts cleared through Chicago Mercantile Exchange | $ 0 | $ 0

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