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Fair Value Measurements - Nonrecurring (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017 | Dec. 31, 2016
Assets and liabilities measured at fair value |  |  |  |
Valuation allowance | $ 588 | $ 144 |  |
Carrying value of other real estate owned | 7,063 | 8,371 | $ 13,481 | $ 11,916
OREO Valuation allowance | 8,099 | 8,208 | $ 9,659 | $ 9,982
Impaired loans |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Valuation allowance |  | 5,300 |  |
Nonrecurring |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Total | 15,997 | 13,484 |  |
Nonrecurring | Impaired loans |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Total | 8,934 | 5,113 |  |
Valuation allowance | 588 | 144,000,000 |  |
Increase (decrease) of specific allocations within the provision for loan losses | 444 | 856,000,000 |  |
Nonrecurring | Impaired loans | Carrying Amount |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Total | 9,500 |  |  |
Nonrecurring | Other real estate owned |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Total | 7,063 | 8,371 |  |
Carrying value of other real estate owned | 7,100 | 8,400 |  |
Outstanding balance | 16,100 | 17,500 |  |
OREO Valuation allowance | 8,100 | 8,200 |  |
OREO participations | 937,000,000 | 937,000 |  |
Nonrecurring | Level 3 |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Total | 15,997 | 13,484 |  |
Nonrecurring | Level 3 | Impaired loans |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Total | 8,934 | 5,113 |  |
Nonrecurring | Level 3 | Other real estate owned |  |  |  |
Assets and liabilities measured at fair value |  |  |  |
Total | $ 7,063 | $ 8,371 |  |

X
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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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