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Derivative Financial Instruments - Summary of Fair Value of Derivative Financial Instruments (Detail) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
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Derivative [Line Items] |  |
Total derivative assets | $ 140,201,000 | $ 51,301,000
Total derivative liabilities | 18,187,000 | 12,393,000
Fair values of counterparty interest rate swaps | 0 |
Interest rate contracts net adjustment | 100,400,000 | 31,600,000
Derivatives designated as hedging instruments |  |
Derivative [Line Items] |  |
Total derivative assets | 17,202,000 | 7,157,000
Total derivative liabilities | 1,988,000 | 1,046,000
Derivatives designated as hedging instruments | Interest rate contracts | Other assets |  |
Derivative [Line Items] |  |
Total derivative assets | 17,202,000 | 7,157,000
Derivatives designated as hedging instruments | Interest rate contracts | Other liabilities |  |
Derivative [Line Items] |  |
Total derivative liabilities | 1,988,000 | 1,046,000
Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Total derivative assets | 122,999,000 | 44,144,000
Total derivative liabilities | 16,199,000 | 11,347,000
Derivatives not designated as hedging instruments | Interest rate contracts | Other assets |  |
Derivative [Line Items] |  |
Total derivative assets | 113,300,000 | 42,224,000
Derivatives not designated as hedging instruments | Interest rate contracts | Other liabilities |  |
Derivative [Line Items] |  |
Total derivative liabilities | 13,676,000 | 10,883,000
Derivatives not designated as hedging instruments | Mortgage contracts | Other assets |  |
Derivative [Line Items] |  |
Total derivative assets | 9,375,000 | 1,702,000
Derivatives not designated as hedging instruments | Mortgage contracts | Other liabilities |  |
Derivative [Line Items] |  |
Total derivative liabilities | 2,335,000 | 354,000
Derivatives not designated as hedging instruments | Foreign currency contracts | Other assets |  |
Derivative [Line Items] |  |
Total derivative assets | 324,000 | 218,000
Derivatives not designated as hedging instruments | Foreign currency contracts | Other liabilities |  |
Derivative [Line Items] |  |
Total derivative liabilities | $ 188,000 | $ 110,000

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