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Derivative Financial Instruments - Schedule of Amounts Related to Non-Hedging Interest Rate and Commodity Derivatives (Detail) - Non Designated as Hedging Instrument [Member] - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2020 | Mar. 31, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Interest Rate Contract [Member] | Other Non-Interest Income [Member] |  |  |  |  |
Other Non Interest Income Non Hedging Interest Rate Derivatives [Line Items] |  |  |  |  |
Amount of gain (loss) included in income (expense) | $ 280 |  | $ 215 | $ 2,615 | $ 1,188
Interest Rate Contract [Member] | Other Non-Interest Expense [Member] |  |  |  |  |
Other Non Interest Income Non Hedging Interest Rate Derivatives [Line Items] |  |  |  |  |
Amount of gain (loss) included in income (expense) | 1 |  | 0 | 1 | 0
Commodity Contract [Member] | Other Non-Interest Income [Member] |  |  |  |  |
Other Non Interest Income Non Hedging Interest Rate Derivatives [Line Items] |  |  |  |  |
Amount of gain (loss) included in income (expense) | 379 |  | 109 | 1,057 | 322
Foreign Currency Derivative Contracts [Member] | Other Non-Interest Income [Member] |  |  |  |  |
Other Non Interest Income Non Hedging Interest Rate Derivatives [Line Items] |  |  |  |  |
Amount of gain (loss) included in income (expense) | 10 |  | 12 | 28 | 41
Put Option [Member] | Other Non-Interest Income [Member] |  |  |  |  |
Other Non Interest Income Non Hedging Interest Rate Derivatives [Line Items] |  |  |  |  |
Amount of gain (loss) included in income (expense) | $ 0 | $ 6,000 | $ 0 | $ 5,980 | $ 0

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- Definition Other Non Interest Income Non Hedging Interest Rate Derivatives [Line Items] + References No definition available. + Details
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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