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Off-Balance Sheet Arrangements Commitments Guarantees and Contingencies (Narrative) (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Commitments And Guarantees [Line Items] |  |  |
Credit card guarantees | $ 8,600 | $ 9,100 |
Fully collateralized credit card guarantees | 962 | 8,200 |
Frost Wealth Advisors [Member] |  |  |
Commitments And Guarantees [Line Items] |  |  |
Fair value of off-balance sheet managed and custody assets | $ 43,300,000 | $ 38,600,000 | $ 37,800,000

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- Definition Collateralized Credit Card Guarantees + References No definition available. + Details
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- Definition Commitments And Guarantees [Line Items] + References No definition available. + Details
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- Definition Credit Card Guarantees + References No definition available. + Details
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- Definition The fair value of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 + Details
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- Details
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