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Financial Instruments with Off-Balance Sheet Risk and Derivative Transactions - Commitments (Details) - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | ---
Company's contractual commitments due to letters of credit |  |
Total letters of credit | $ 12,447 | $ 13,511
Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 243 | 315
Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 12,204 | 13,196
Borrower |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 12,025 | 12,891
Borrower | Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 243 | 220
Borrower | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 11,782 | 12,671
Borrower | Financial standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 3,925 | 4,184
Borrower | Financial standby | Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 177 | 137
Borrower | Financial standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 3,748 | 4,047
Borrower | Commercial standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 122 | 126
Borrower | Commercial standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 122 | 126
Borrower | Performance standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 7,978 | 8,581
Borrower | Performance standby | Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 66 | 83
Borrower | Performance standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 7,912 | 8,498
Nonborrower | Performance standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 422 | 620
Nonborrower | Performance standby | Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit |  | 95
Nonborrower | Performance standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | $ 422 | $ 525

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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 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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