Allowance for credit losses (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of the period	$ 72,751	$ 72,976	$ 88,547
Provision (reversal of provision) for loan losses	6,895us-gaap_ProvisionForLoanAndLeaseLosses	(1,598)us-gaap_ProvisionForLoanAndLeaseLosses	(8,343)us-gaap_ProvisionForLoanAndLeaseLosses
Loan recovenies and other	29	1,373	262
Loans written-off	0	0	(7,490)
Balance at end of the period	79,675	72,751	72,976
Components:
Generic allowance	77,260blx_GenericAllowance	71,797blx_GenericAllowance	72,976blx_GenericAllowance
Specific allowance	2,415blx_SpecificAllowance	954blx_SpecificAllowance	0blx_SpecificAllowance
Total allowance for loan losses	79,675	72,751	72,976
Corporations [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of the period	31,516	32,488	48,865
Provision (reversal of provision) for loan losses	11,250	(972)	(8,887)
Loan recovenies and other	0	0	0
Loans written-off	0	0	(7,490)
Balance at end of the period	42,766	31,516	32,488
Components:
Generic allowance	40,482	30,562	32,488
Specific allowance	2,284	954	0
Total allowance for loan losses	42,766	31,516	32,488
Banking and financial institutions [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of the period	30,865	28,836	30,523
Provision (reversal of provision) for loan losses	647	656	(1,704)
Loan recovenies and other	0	1,373	17
Loans written-off	0	0	0
Balance at end of the period	31,512	30,865	28,836
Components:
Generic allowance	31,512	30,865	28,836
Specific allowance	0	0	0
Total allowance for loan losses	31,512	30,865	28,836
Middle market companies [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of the period	10,369	10,887	8,952
Provision (reversal of provision) for loan losses	(5,001)	(518)	1,690
Loan recovenies and other	29	0	245
Loans written-off	0	0	0
Balance at end of the period	5,397	10,369	10,887
Components:
Generic allowance	5,266	10,369	10,887
Specific allowance	131	0	0
Total allowance for loan losses	5,397	10,369	10,887
Sovereign [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of the period	1	765	207
Provision (reversal of provision) for loan losses	(1)	(764)	558
Loan recovenies and other	0	0	0
Loans written-off	0	0	0
Balance at end of the period	0	1	765
Components:
Generic allowance	0	1	765
Specific allowance	0	0	0
Total allowance for loan losses	$ 0	$ 1	$ 765

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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

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-Number Topic 6

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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

-Publisher FASB

-Name Accounting Standards Codification

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