Represents the limit of the restricted stock unit compensation as a percentage to the total annual compensation of the award.

No definition available.

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- Definition

The minimum number of non-employee members of the Board authorized to issue restricted stock units. The members are appointed by the Board each of whom is both a non-employee director and an outside director.

+ References

No definition available.

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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (k)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Long Term Restricted Stock Units (Details) (2009 International Bancshares Corporation Long-Term Restricted Stock Unit Plan, USD $)	12 Months Ended						1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2009 item
CPP-compliant long-term RSUs
Long-Term Restricted Stock Units
Restricted stock compensation limit as a percentage to the total annual compensation of the President	33.00%
CPP-compliant long-term RSUs granted for performance in 2012
Long-Term Restricted Stock Units
Compensation cost		$ 425,000
CPP-compliant long-term RSUs granted for performance in 2011
Long-Term Restricted Stock Units
Compensation cost				400,000
Cash amounts paid on vesting of awards			572,746
CPP-compliant long-term RSUs granted for performance in 2010
Long-Term Restricted Stock Units
Compensation cost					400,000
Cash amounts paid on vesting of awards		358,782
CPP-compliant long-term RSUs granted for performance in 2009
Long-Term Restricted Stock Units
Compensation cost						250,000
Cash amounts paid on vesting of awards	591,344	$ 262,842
Restricted Stock Units (RSUs)
Long-Term Restricted Stock Units
Minimum number of non-employee members of the Board needed to authorize restricted stock units							2