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Derivatives, Hedging Activities and Financial Instruments with Off-Balance Sheet Risk - Commitments (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Company's contractual commitments due to letters of credit |  |
Total letters of credit | $ 12,273 | $ 12,278
Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 533 | 418
Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 11,740 | 11,860
Borrower |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 12,131 | 12,136
Borrower | Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 533 | 418
Borrower | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 11,598 | 11,718
Borrower | Financial standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 4,444 | 3,947
Borrower | Financial standby | Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 292 | 177
Borrower | Financial standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 4,152 | 3,770
Borrower | Commercial standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 354 | 354
Borrower | Commercial standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 354 | 354
Borrower | Performance standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 7,333 | 7,835
Borrower | Performance standby | Fixed |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 241 | 241
Borrower | Performance standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 7,092 | 7,594
Nonborrower | Performance standby |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | 142 | 142
Nonborrower | Performance standby | Variable |  |
Company's contractual commitments due to letters of credit |  |
Total letters of credit | $ 142 | $ 142

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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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