Financial instruments with off-balance sheet credit risk (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012
Within 1 year	$ 219,421
From 1 to 2 years	1,000
From 2 to 5 years	13,791
After 5 years	664
Maturity Of Banks Outstanding Financial Instruments With Off Balance Sheet Credit Risk	$ 234,876

It represent Banks outstanding financial instruments with off-balance sheet credit risk.

No definition available.

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It represent Banks outstanding financial instruments with off-balance sheet credit risk, maturity after five years.

No definition available.

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It represent Banks outstanding financial instruments with off-balance sheet credit risk, maturity From one To Two years.

No definition available.

Name:	blx_BanksOutstandingFinancialInstrumentsWithOffBalanceSheetCreditRiskMaturityFromOneToTwoYeaars
Namespace Prefix:	blx_
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It represent Banks outstanding financial instruments with off-balance sheet credit risk, maturity From Two To Five years.

No definition available.

Name:	blx_BanksOutstandingFinancialInstrumentsWithOffBalanceSheetCreditRiskMaturityFromTwoToFiveYeaars
Namespace Prefix:	blx_
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It represent Banks outstanding financial instruments with off-balance sheet credit risk, maturity within year one.

No definition available.

Name:	blx_BanksOutstandingFinancialInstrumentsWithOffBalanceSheetCreditRiskMaturityWithInYearOne3
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Data Type:	xbrli:monetaryItemType
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