v3.25.3

Investment Securities, Equity Securities with Readily Determinable Fair Values and Other Investments - Unrealized Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Available for sale:
Fair value, less than 12 months	$ 47,131	$ 610,825
Unrealized losses, less than 12 Months	(1,254)	(6,515)
Fair value, 12 months or more	3,179,415	3,416,137
Unrealized losses, 12 Months or More	(358,661)	(487,068)
Fair value, Total	3,226,546	4,026,962
Unrealized losses, Total	(359,915)	(493,583)
Residential mortgage-backed securities
Available for sale:
Fair value, less than 12 months	5,651	544,375
Unrealized losses, less than 12 Months	(11)	(4,126)
Fair value, 12 months or more	3,096,713	3,358,586
Unrealized losses, 12 Months or More	(353,600)	(485,044)
Fair value, Total	3,102,364	3,902,961
Unrealized losses, Total	(353,611)	(489,170)
Obligations of states and political subdivisions
Available for sale:
Fair value, less than 12 months	41,480	66,450
Unrealized losses, less than 12 Months	(1,243)	(2,389)
Fair value, 12 months or more	82,702	57,551
Unrealized losses, 12 Months or More	(5,061)	(2,024)
Fair value, Total	124,182	124,001
Unrealized losses, Total	$ (6,304)	$ (4,413)

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.

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INTERNATIONAL BANCSHARES CORP 10-Q