v3.24.1.1.u2
Cover
May 20, 2024
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date May 20, 2024
Entity File Number 000-9439
Entity Registrant Name INTERNATIONAL BANCSHARES CORPORATION
Entity Central Index Key 0000315709
Entity Tax Identification Number 74-2157138
Entity Incorporation, State or Country Code TX
Entity Address, Address Line One 1200 San Bernardo
Entity Address, City or Town Laredo
Entity Address, State or Province TX
Entity Address, Postal Zip Code 78040-1359
City Area Code 956
Local Phone Number 722-7611
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock, $1.00 par value
Trading Symbol IBOC
Security Exchange Name NASDAQ
Entity Emerging Growth Company false