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Financial Instruments with Off-Statement of Condition Risk and Concentrations of Credit Risk (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015
Maximum |  |
Financial amounts of instruments, whose contract amounts represent credit risks |  |
Credit risk commitment, maximum expiration date | 1 year |
Commitments to Extend Credit |  |
Financial amounts of instruments, whose contract amounts represent credit risks |  |
Outstanding amount of financial instruments whose, contract amounts represent credit risks | $ 2,262,717,000 |
Credit Card Lines |  |
Financial amounts of instruments, whose contract amounts represent credit risks |  |
Outstanding amount of financial instruments whose, contract amounts represent credit risks | 18,531,000 |
Standby Letters of Credit |  |
Financial amounts of instruments, whose contract amounts represent credit risks |  |
Outstanding amount of financial instruments whose, contract amounts represent credit risks | 88,504,000 |
Commercial Letters of Credit |  |
Financial amounts of instruments, whose contract amounts represent credit risks |  |
Outstanding amount of financial instruments whose, contract amounts represent credit risks | 4,650,000 |
Unsecured Letters of Credit |  |
Financial amounts of instruments, whose contract amounts represent credit risks |  |
Guarantee obligations, maximum exposure | 88,504,000 |
Unsecured letters of credit | $ 40,738,000 | $ 37,454,000

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- Definition Represents the maximum fixed expiration date upon which commitments are set to expire. + References No definition available. + Details
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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=73719730&loc=d3e13433-108611 + Details
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Balance Type: | credit
Period Type: | instant

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + 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 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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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
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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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Details
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- Details
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- Details
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- Details
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Period Type: |

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- Details
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- Details
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