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Fair Value Measurement - Assets Measured at Estimated Fair Value on Nonrecurring Basis by Fair Value Hierarchy (Detail) - Fair Value, Measurements, Nonrecurring - USD ($) | Sep. 30, 2016 | Dec. 31, 2015
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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] | 9,000,000 | 9,373,000
Other real estate owned | [1] | 181,000 | 158,000
Mortgage servicing rights | [1] | 3,253,000 | 3,396,000
Total Assets | [1] | 12,434,000 | 12,927,000
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] | 9,000,000 | 9,373,000
Other real estate owned | [1] | 181,000 | 158,000
Mortgage servicing rights | [1] | 3,253,000 | 3,396,000
Total Assets | [1] | $ 12,434,000 | $ 12,927,000
[1] | This table represents only the nonrecurring items that are recorded at fair value in our financial statements.

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