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Fair Value Measurements - Assets Measured at Estimated Fair Value on Nonrecurring Basis by Fair Value Hierarchy (Detail) - Fair Value, Measurements, Nonrecurring [Member] - USD ($) $ in Thousands | Jun. 30, 2015 | Dec. 31, 2014
--- | --- | ---
ASSETS |  |
Loans held for sale | $ 2,900 |
Impaired loans | 13,913 | $ 12,916
Other Assets, Fair Value Disclosure | 747 | 117
Mortgage servicing rights | 721 | 1,176
Total Assets | 18,281 | 14,209
Level 3 [Member] |  |
ASSETS |  |
Loans held for sale | 2,900 |
Impaired loans | 13,913 | 12,916
Other Assets, Fair Value Disclosure | 747 | 117
Mortgage servicing rights | 721 | 1,176
Total Assets | $ 18,281 | $ 14,209

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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=36462937&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=56950315&loc=d3e122625-111746 + Details
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