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Derivative Financial Instruments (Summary Amounts Included In Consolidated Statement Of Income Related To Derivatives) (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Interest rate swaps and caps | Trading gains, net |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | $ 4,024 | $ 428
Mortgage banking derivatives | Mortgage banking revenue |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | (7,369) | (17,479)
Foreign exchange contracts | Trading gains, net |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | 0 | (5)
Covered call options | Fees from covered call options |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gains (losses) on derivative instruments | $ 3,742 | $ 0

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959 + Details
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