Deposits - Additional Information About Corporation's Deposits (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Deposit Liability [Line Items]
Deposits from foreign sources (primarily Mexico)	$ 1,087,494	$ 1,061,701
Non-interest-bearing public funds deposits	13,754,985	14,926,094
Interest-bearing public funds deposits	27,051,501	26,994,474
Total deposits not covered by deposit insurance	21,378,776	22,393,786
Time deposits not covered by deposit insurance	2,606,127	2,339,716
Public Funds [Member]
Deposit Liability [Line Items]
Non-interest-bearing public funds deposits	442,355	675,016
Interest-bearing public funds deposits	$ 697,824	$ 630,455

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
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The aggregate of all foreign interest-bearing and noninterest-bearing deposit liabilities.

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