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Fair Values of Assets and Liabilities - Schedule of Assets Measured on Non-Recurring Basis (Detail) - USD ($) $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | $ 833,517 | $ 829,181
Fair Value, Measurements, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 36,621 | 38,669
Other real estate owned | 6,083 | 7,566
Total Assets | 42,704 | 46,235
Level 1 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | 0 | 0
Level 1 [Member] | Fair Value, Measurements, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 0 | 0
Other real estate owned | 0 | 0
Total Assets | 0 | 0
Level 2 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | 795,656 | 793,289
Level 2 [Member] | Fair Value, Measurements, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 19,878 | 18,679
Other real estate owned | 6,083 | 7,566
Total Assets | 25,961 | 26,245
Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total Assets | 37,861 | 35,892
Level 3 [Member] | Fair Value, Measurements, Nonrecurring [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 16,743 | 19,990
Other real estate owned | 0 | 0
Total Assets | $ 16,743 | $ 19,990

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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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