International Operations (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Loans:
Accrued interest receivable	$ 31,461,000us-gaap_InterestReceivable	$ 30,654,000us-gaap_InterestReceivable
International banking services
Loans:
Commercial	150,078,000	142,145,000
Others	35,143,000	39,697,000
Total loans	185,221,000	181,842,000
Less allowance for probable loan losses	(1,060,000)	(1,133,000)
Net loans	184,161,000	180,709,000
Accrued interest receivable	702,000	617,000
Outstanding standby and commercial letters of credit	114,672,000
Revenues	$ 6,034,000	$ 6,085,000	$ 7,714,000

Interest and fee income generated by commercial and consumer loans, made by foreign branches of the reporting entity, which may include loans to foreign governments, foreign banks and other financial institutions, commercial and industrial entities, and citizens of not domiciled in the same country as the reporting entity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.1)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 1

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.8)

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-Section 02

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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The allowance for foreign loan and lease losses represents the reserve to cover probable credit losses related to specifically identified foreign loans and leases, as well as probable credit losses inherent in the remainder of the foreign loan portfolio as of the balance sheet date. For banks, include currently required allocated transfer risk reserves. Include carryover of or adjustments to the allowance for foreign loan losses in connection with business combinations determined to be appropriate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (SX 210.9-03.7(d))

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-Name Staff Accounting Bulletin (SAB)

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- Definition

Amount before allowance of loans to entities involved in commercial enterprises, not originated within the country of domicile of the reporting entity. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

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Amount before allowance of loans, not otherwise specified in the taxonomy, not originated within the country of domicile of the reporting entity. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Reflects the net carrying amount of foreign loans and leases held in portfolio, after deducting deferred income, but before deducting the allowance for losses on foreign loans and leases.

+ References

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Amount after allowance and deduction of deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts, of loans and leases to borrowers not within the country of domicile of the reporting entity. Excludes loans and leases covered under loss sharing agreements.

+ References

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