Deposits - Additional Information About Corporation's Deposits (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Deposit Liability [Line Items]
Deposits from foreign sources (primarily Mexico)	$ 1,079,651	$ 1,048,943
Non-interest-bearing public funds deposits	14,631,456	17,598,234
Interest-bearing public funds deposits	26,360,779	26,355,962
Total deposits not covered by deposit insurance	21,403,451	24,168,709
Time deposits not covered by deposit insurance	2,122,421	477,489
Public Funds [Member]
Deposit Liability [Line Items]
Non-interest-bearing public funds deposits	403,963	788,040
Interest-bearing public funds deposits	$ 595,477	$ 758,761

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 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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Amount of uninsured deposit liability.

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The aggregate of all foreign interest-bearing and noninterest-bearing deposit liabilities.

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