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Fair Value Measurements - Assets Measured at Estimated Fair Value on Nonrecurring Basis by Fair Value Hierarchy (Details) - Fair Value, Measurements, Nonrecurring - USD ($) | Jun. 30, 2018 | Dec. 31, 2017
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Liabilities measured at fair value on a nonrecurring basis |  | $ 0 | $ 0
ASSETS |  |  |
Impaired loans | [1] | 5,487,000 | 6,759,000
Other real estate owned | [1] | 2,719,000 | 444,000
Mortgage servicing rights | [1] | 89,000 | 178,000
Total Assets | [1] | 8,295,000 | 7,381,000
Level 1 |  |  |
ASSETS |  |  |
Impaired loans | [1] | 0 | 0
Other real estate owned | [1] | 0 | 0
Mortgage servicing rights | [1] | 0 | 0
Total Assets | [1] | 0 | 0
Level 2 |  |  |
ASSETS |  |  |
Impaired loans | [1] | 0 | 0
Other real estate owned | [1] | 0 | 0
Mortgage servicing rights | [1] | 0 | 0
Total Assets | [1] | 0 | 0
Level 3 |  |  |
ASSETS |  |  |
Impaired loans | [1] | 5,487,000 | 6,759,000
Other real estate owned | [1] | 2,719,000 | 444,000
Mortgage servicing rights | [1] | 89,000 | 178,000
Total Assets | [1] | $ 8,295,000 | $ 7,381,000
[1] | This table represents only the nonrecurring items that are recorded at fair value in our financial statements.

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