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Commitments - Summary of Financial Instrument Commitments (Details) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Fixed |  |
Financial instrument commitments |  |
Financial instrument commitments | $ 315 | $ 126
Loan commitments | 68,996 | 71,016
Fixed | Borrower |  |
Financial instrument commitments |  |
Financial instrument commitments | 220 | 126
Fixed | Borrower | Financial standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 137 | 60
Fixed | Borrower | Performance standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 83 | 66
Fixed | Nonborrower |  |
Financial instrument commitments |  |
Financial instrument commitments | 95 |
Fixed | Nonborrower | Performance standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 95 |
Variable |  |
Financial instrument commitments |  |
Financial instrument commitments | 13,196 | 11,544
Loan commitments | 270,989 | 197,909
Variable | Borrower |  |
Financial instrument commitments |  |
Financial instrument commitments | 12,672 | 10,969
Variable | Borrower | Financial standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 4,047 | 3,572
Variable | Borrower | Commercial standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 126 | 47
Variable | Borrower | Performance standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 8,499 | 7,350
Variable | Nonborrower |  |
Financial instrument commitments |  |
Financial instrument commitments | 524 | 575
Variable | Nonborrower | Performance standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 524 | 575
Total. |  |
Financial instrument commitments |  |
Financial instrument commitments | 13,511 | 11,670
Loan commitments | 339,985 | 268,925
Total. | Borrower |  |
Financial instrument commitments |  |
Financial instrument commitments | 12,892 | 11,095
Total. | Borrower | Financial standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 4,184 | 3,632
Total. | Borrower | Commercial standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 126 | 47
Total. | Borrower | Performance standby |  |
Financial instrument commitments |  |
Financial instrument commitments | 8,582 | 7,416
Total. | Nonborrower |  |
Financial instrument commitments |  |
Financial instrument commitments | 619 | 575
Total. | Nonborrower | Performance standby |  |
Financial instrument commitments |  |
Financial instrument commitments | $ 619 | $ 575

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