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Financial Instruments with Off-Statement of Condition Risk and Concentrations of Credit Risk (Details) (USD $) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2012 Maximum | Dec. 31, 2012 Commitments to extend credit | Dec. 31, 2012 Credit card lines | Dec. 31, 2012 Standby letters of credit | Dec. 31, 2012 Commercial letters of credit | Dec. 31, 2012 Unsecured letters of credit | Dec. 31, 2011 Unsecured letters of credit
Financial amounts of instruments, whose contract amounts represent credit risks |  |  |  |  |  |  |
Outstanding amount of financial instruments whose, contract amounts represent credit risks |  | $ 1,481,285,000 | $ 66,243,000 | $ 89,129,000 | $ 13,753,000 |  |
Guarantee obligations, maximum exposure |  |  |  |  |  | 89,129,000 |
Unsecured letters of credit |  |  |  |  |  | $ 28,383,000 | $ 27,991,000
Credit risk commitment, maximum expiration date | 1 year |  |  |  |  |  |

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- Definition The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611 + Details
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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Interpretation (FIN) -Number 45 -Paragraph 13 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 + Details
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Balance Type: | credit
Period Type: | instant

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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. + Details
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