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Fair Value Measurement - Assets Measured at Estimated Fair Value on Nonrecurring Basis by Fair Value Hierarchy (Details) - Fair Value, Measurements, Nonrecurring - USD ($) | Jun. 30, 2017 | Dec. 31, 2016
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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 |  |  |
Loans held for sale | [1] | 0 | 1,802,000
Impaired loans | [1] | 22,551,000 | 10,329,000
Other real estate owned | [1] | 391,000 | 396,000
Mortgage servicing rights | [1] | 508,000 | 4,098,000
Total Assets | [1] | 23,450,000 | 16,625,000
Level 1 |  |  |
ASSETS |  |  |
Loans held for sale | [1] | 0 | 0
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 |  |  |
Loans held for sale | [1] | 0 | 0
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 |  |  |
Loans held for sale | [1] | 0 | 1,802,000
Impaired loans | [1] | 22,551,000 | 10,329,000
Other real estate owned | [1] | 391,000 | 396,000
Mortgage servicing rights | [1] | 508,000 | 4,098,000
Total Assets | [1] | $ 23,450,000 | $ 16,625,000
[1] | This table represents only the nonrecurring items that are recorded at fair value in our financial statements.

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746 + Details
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