Investment securities (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 54,180	$ 33,759
Unrealized Gross Gain	73	8
Unrealized Gross Loss	958	133
Fair Value	53,295	33,634
Corporate Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	41,177	20,752
Unrealized Gross Gain	33	8
Unrealized Gross Loss	958	18
Fair Value	40,252	20,742
Corporate Debt Securities [Member] \| Brazil [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	17,824
Unrealized Gross Gain	0
Unrealized Gross Loss	958
Fair Value	16,866
Corporate Debt Securities [Member] \| Costa Rica [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost		2,000
Unrealized Gross Gain		0
Unrealized Gross Loss		0
Fair Value		2,000
Corporate Debt Securities [Member] \| Honduras [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost		4,118
Unrealized Gross Gain		0
Unrealized Gross Loss		0
Fair Value		4,118
Corporate Debt Securities [Member] \| Panama [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	23,353	14,634
Unrealized Gross Gain	33	8
Unrealized Gross Loss	0	18
Fair Value	23,386	14,624
Sovereign Debt [Member] \| Colombia [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	13,003	13,007
Unrealized Gross Gain	40	0
Unrealized Gross Loss	0	115
Fair Value	$ 13,043	$ 12,892

Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

No definition available.

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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- Definition

Amount of unrecognized gain before loss on investments in held-to-maturity securities.

+ References

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Amount of unrecognized loss before gain on investments in held-to-maturity securities. Excludes write-down for other than temporary impairment (OTTI).

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